2025 marks the 20^th anniversary of the launch of zHome, the first ILFI certified Zero Energy community in the United States.  This groundbreaking project aimed to make zero carbon living mainstream by demonstrating an array of new, but available, technologies under one roof.  Over the last 20 years, the solutions zHome showcased have become much better, more accessible, and less expensive.  

Today, the climate crisis is advancing, but so are the solutions. Living a near-zero carbon life is now within reach with manageable efforts. Here’s how:

• Energy Efficiency Solutions: From energy monitors to LED lighting and vacancy switches, affordable efficiency solutions are readily available at your local home improvement store. New products are aggressively reducing standby energy use, making vampire loads a thing of the past.
• Renewable Energy: In most parts of the country, generating your own renewable electricity is now cheaper per kWh than purchasing fossil-fuel-generated electricity from the utility. Additionally, many utilities have a 100% renewable electricity purchase option is available for a nominal cost.
• Heat Pumps: Heat pumps are scaling rapidly and decreasing in cost, including models suitable for cold climates.
• Sustainable Mobility: Infrastructure for walking, biking, and micromobility is improving. Public transit is expanding, and electric vehicles (EVs) have become mainstream. EVs, combined with renewable electricity, offer zero-carbon mobility and are increasingly affordable.
• Sustainable Diets: Vegetarian and low-carbon diets are more accessible and easier to adopt, contributing to lower carbon footprints.

For decades, advocacy and professional communities have diligently crafted a range of sustainability and climate-positive solutions that are now ready for prime time. These innovations enable mainstream individuals to adopt climate-positive lifestyles effectively.

Reflecting on nearly two decades since the zHome project, the collective impact of these communities is substantial. However, many climate-conscious individuals, myself included, still struggle with reducing their carbon footprints. Despite implementing a passive house retrofit, installing a solar array, doing our best to live simply, and owning an electric vehicle, my family’s carbon footprint was higher than expected. Factors like air travel, meat consumption, and high material consumption offset our climate-friendly efforts.

Many in the climate movement excel in certain areas while falling short in others—vegans who love to travel long distances by air, beef eaters who drive gas-guzzlers but rarely leave their locale, or climate activists who attribute their footprint to systemic issues. Why is it challenging to achieve a low-carbon lifestyle despite its relative ease?

The one-two punch of COVID-19 and significant social, political, and cultural shifts have undoubtedly played a role. However, I believe the primary barrier is a lack of accessible information. People are busy and often unsure where to start. Even within decarbonization communities, knowing the right actions can be difficult. After calculating my carbon footprint, I found no comprehensive source prioritizing actionable steps. Many resources were either too broad or too specific.

To address this, I created a website which is a one-stop shop for reducing personal climate impact. The platform is organized around two key themes—what to do and why to do it—covering essential areas like home, mobility, food, and consumption. Prioritized action tiers and a downloadable action checklist help users make meaningful progress.

Launched three months ago, Climate Responsible has received positive feedback and recognition from environmental leaders like Denis Hayes and Bill McKibben. Although the platform is Western and North America-centric, it focuses on places with the largest footprints and greatest responsibility. Amidst global turmoil, those who can act must do so. Collective action can create a virtuous cycle of mainstreaming and normalizing sustainable practices, ultimately reducing costs and improving market readiness.

Climate Responsible isn’t about debating the reality of climate change or the ethics of inaction. It’s for those who understand the urgency of our slow-moving crisis and are ready to take responsibility. I hope you find it helpful and, most importantly, use it. Personal decarbonization within our movement can drive market change, set examples, and catalyze widespread transformation.

Check it out: Climate Responsible. Be sure and sign up for my newsletter if you’d like to stay updated

Editor’s Note: Brad Liljequist directed the Zero Energy and Zero Carbon programs at ILFI from 2013-2018 and the Living Community Challenge from 2014-2015. Between 2008-2011, he developed the first ILFI certified Energy Petal and Zero Energy community in the United States, zHome. Today, Brad leads Zero Energy and Zero Carbon efforts for McKinstry, a national construction, consulting, and energy services company based in Seattle. McKinstry has just opened the South Landing development in Spokane, Washington, which is home to the zero energy, zero carbon Catalyst building that brings ILFI Zero Energy and Zero Carbon certification to the mainstream (detailed project profile here). We thought it appropriate to get his perspectives on Zero Energy and Zero Carbon in the lead-up to the Zero Carbon Conference. 

Zero Energy and Zero Carbon (referred to for the rest of this blog as Zero Energy + Carbon), taken together, have always been an evolving concept, pushing the outer limits of climate solutions in the built environment. They have been remarkably powerful visions for “what good looks like,” driving rapid progress in efficiency and building-connected renewables in a little over a decade of significant use.  Yet I believe it is time for us to evolve the concept yet again, to accelerate and realize the full vision of a thriving society, 100% climate positive, efficiently run and renewably powered. In this blog I reflect on where we’ve come, where we are, and where I think we need to go. I also share a few thoughts about how Zero Energy + Carbon should be fully integrated into the mainstream design and development process. I will also draw a few examples from McKinstry’s Catalyst building, which represents many of these next generation elements.  

A brief history of ILFI Zero Energy and Zero Carbon

The term “zero energy” first surfaced in the sustainable building world in the early 2000s. At its simplest, a zero-energy building renewably generated at least an equal amount of energy as it used and was assumed to be connected to the energy grid (rather than off-grid). To achieve this goal, the building had to be extremely efficient. Zero Energy was the core concept undergirding the Energy Petal of the Living Building Challenge launched in 2008, which also included critical concepts such as no combustion. In 2012, ILFI introduced the world’s first Zero Energy Certification. Initially, this certification included several elements of the Living Building Challenge, but in an effort to simplify the Zero Energy Certification, these elements were later removed. In 2016, recognizing that Zero Energy was impossible to achieve for the majority of commercial buildings due to intensity of use (such as labs or hospitals) or density (midrise and higher), we created the offsite renewable pathway, to enable offsetting renewables to be placed away from the building, so long as the building maximized efficiency and onsite renewables and the offsite renewables were appropriately sited.

Then in 2018, we entered a new era of Zero Carbon certified buildings. This certification recognized the many parts of the world where true utility-scale renewable power purchases were possible, and combined this with aggressive, but not outer-limit, type efficiency. Later that year, embodied carbon requirements were also added to the Zero Carbon Certification to account for the rapid shift in recognition of this important topic. 

Zero Energy + Carbon have proved remarkably effective at broadening the vision and understanding of climate-positive buildings, expanding the audience for super-efficient and renewable integrated buildings beyond energy and green building geeks (sorry, that’s what most of us are!). I still reflect on the 10,000 people who came out to see zHome – the first certified Zero Energy community in the United States – and how “zero energy” was on most of their lips. It captured, and still captures, the imagination. 

Zero Energy + Carbon are still works-in-progress, however. Core concepts undergirding the ILFI certifications are “what good looks like” and biophilic, ecosystem-type solutions. I think the most compelling critique of Zero Energy + Carbon historically has been that they have essentially benefitted from the grid without a reciprocal recognition of the needs of the grid. The end game vision is not one of autonomous buildings, using the grid for its independent benefit, but rather an energy ecosystem of buildings, transportation, industry, and renewable generation, sharing thermal and electrical resources that are generated in planet positive ways. Zero energy definitions based on source energy are a nod in this direction, even though they were imperfectly applied. I believe the future of Zero Energy + Carbon will be inclusive of this holistic ecosystem view. 

The Present and Future of Zero Energy + Carbon

OK then – without further ado – here are my thoughts on where we stand and where we need to go:

Zero Energy + Carbon have arrived in the mainstream consciousness. In 2016, a handful of us brainstormed how to get “zero energy” said publicly during the U.S. presidential campaign. Apart from those efforts, a little known fact is that Hilary Clinton visited the IBEW facility in City of Commerce, CA, which was targeting zero energy, and did talk at some length about zero energy buildings in a speech there (unfortunately recorded only by a shaky cell phone video, apparently no longer on YouTube), but that was it. Today, “net zero” in a holistic sense is the backbone of the Biden campaign and the Green New Deal. Official corporate policy, well represented by Microsoft’s public announcement this year of committing to ILFI Zero Carbon certification for its Puget Sound campus refresh and Bay Area campus, and Jeff Bezos’ announcement about Climate Pledge Arena and its declared plan for ILFI Zero Carbon certification, are key signifiers that the state of Zero Energy + Carbon has arrived in the mainstream consciousness. 

ILFI deserves great credit for championing a vision of an all-electric future and weathering the storm of criticism. Throughout my tenure at ILFI, we were regularly encouraged to soften our stance on natural gas, even by other green building organizations. We were told frequently that if we did, we could likely receive substantial financial support from the natural gas industry. I even had the pleasure of sitting as the lone electrification voice on a keynote stage (with five folks from the gas industry) debating the feasibility of an all-electric future. That was a lonely time, and not that long ago, either. Today, leading jurisdictions are starting to limit natural gas expansion, and some combined gas/electric utilities, including Pacific Gas and Electric, are publicly supporting the transition to electricity.  

For the building industry to address the climate crisis, we must also address the building affordability crisis. Productivity in the building sector has been stagnant for decades – unlike every other major economic sector. This means buildings are simply too expensive – making the addition of yet more cost for climate solutions an uphill battle. In turn, this actually opens opportunities to apply deep innovation to reduce cost and carbon at the same time. In the Catalyst building, we were one of the first in the United States to incorporate manufactured cross-laminated timber (CLT) construction in a mid-rise setting, and invented prefabricated multi-service appliances (our patent pending Overcast Solutions Cloud, which integrates lighting, HVAC distribution, low voltage, and IT), substantially reducing our construction cost, while enabling climate positive solutions. Addressing this topic, of course, also helps us address the critical topic of equity in housing and shelter. 

The recent strong pivot to embodied carbon was overdue – but everything else is important too. 2018 brought focus on embodied carbon, which continues unabated. Learning and innovation is happening quickly. This is a very important expansion of effort; however,I believe the idea that somehow the efficiency/renewable nut has been resolved (which I have heard from some) is simply not true. We have come quite far – in many cases the solutions are clear – but we still have so far to go, particularly in the area of complete adoption of leading edge efficiency, renewables, retrofits, and especially the full integration of built environment energy systems and a renewably powered grid.

Zero Energy and Carbon buildings should contribute to a larger beneficial grid ecosystem. Even though Zero Energy + Carbon buildings contribute renewable energy to the grid, they are completely grid-reliant for operations, and do little else that is grid-beneficial. In reality, electric utilities operate under substantial constraints, one being the peak infrastructure capacity needed to provide consistent power. For example, because of their typically outstanding envelopes, Zero Energy + Carbon buildings are uniquely able to retain heat or cold, allowing tempering during grid troughs and thermal retention during grid peaks. This can be taken even further through active thermal storage. The Catalyst building is served by the South Landing Eco-District, a shared energy district heating/cooling plant. Designed to serve up to five different buildings, the South Landing plant includes thermal storage tanks, which will allow the heat pumps and chillers to be run in the middle of the night, when grid demand is its lowest. Instead of running a typical mid-winter morning warm up cycle, when the local utility grid is confronted with its peak annual demand, the South Landing plant will already have tanks full of hot water, which will be circulated to Catalyst and other served buildings. This is of enormous value to the utility, and at scale reshuffles the cost equation to enable zero energy/carbon improvements.

Anyone should be able to choose 100% renewable power from their utility – but offsite renewables for Zero Carbon performance are not straightforward in many areas. Something that is not well understood within green building, even by many energy specialists, is that there is a huge range of availability of truly renewable energy purchasable from the utility. A project that seeks Zero Carbon certification in deregulated energy jurisdictions, such as California or the European Union, can typically enter into a renewable purchase agreement with little hassle and a slight cost premium. Here in Washington State, where electricity must be purchased from the local utility, options are much more limited. Only one utility in the state, Puget Sound Energy, offers a full renewable option (Green Direct). Projects in other utility regions must develop their own offsite projects (the path taken by Catalyst) or pay a substantial premium for participation in complex deal structures out of state, which split the electricity and the associated renewable credits.

We must address the global warming potential of refrigerants immediately. Our movement has been successful in mainstreaming heat pumps. Leading jurisdictions are beginning to codify their use. However, the refrigerants they use, if leaked to the atmosphere, have a very high global warming impact. In particular, variable refrigerant flow systems, while extremely efficient, in some cases use literally tons of refrigerants. While alternative refrigerants are sometimes available, it is important to recognize they may have limitations (such as CO2 heat pumps, which have very particular lift temperature profiles). Refrigerant piping and fittings must be improved to ensure they avoid rupture and leakage over their lives. The industry must work together to understand the true lifecycle of refrigerants, with particular scrutiny to the frequency of leakage and end of life disposal.  At a minimum, refrigerants must be subject to substantially greater scrutiny and regulation.  

Energy storage comes in many forms, some more positive than others. As we create a new renewable world, we need to be eyes wide open to unintended consequences – the “clean natural gas” of a decade ago is the fracking-fraught, explosive, global warming gas of today. Like refrigerants, battery storage has the potential to have negative consequences. At scale, rare materials used in batteries could result in simply moving areas of resource conflict from the Middle East to other parts of the world as demand increases, drawing from both the transportation and building sectors. Thermal and mechanical energy storage are much simpler and avoid these risks. We should work to match the right technologies with the right needs (i.e. high power density with need for light weight, such as in transportation) to minimize these concerns.

The era of natural gas kitchens needs to be over, once and for all. Technology advances and product availability in induction ranges and combi-ovens have made all-electric, highly functional commercial cooking completely feasible. Some major corporations have established all-electric food service as their corporate standard. All-electric kitchens also have a virtuous cycle of efficiency, equipment and space reduction, and equitable health. Induction ranges are extremely efficient at placing heat at the base of the cookware, and thus have very little waste heat, meaning ventilation requirements are lower, and associated makeup heating and cooling is reduced. All-electric kitchen work stations are also smaller than comparable gas based stations. And finally, the burns and heat exhaustion often created for kitchen workers in hot gas kitchens, are significantly less. And of course, as the grid becomes more renewable, so do all-electric kitchens.

In leading jurisdictions, the limits of steady improvements in efficiency are not far away in new construction. In jurisdictions with aggressive codes, where heat pumps, dedicated outdoor systems, vacancy based switching, and improved envelopes are required, the steady 10-20% per innovation/code cycle drop we’ve seen for some time is likely to change within the decade. On a recent potential zero carbon project, we found that with a heat pump/DOAS baseline, after inclusion of all-electric kitchens, excellent air sealing, and plug load management, substantial costs with extremely long paybacks are needed to achieve a 10-15% improvement from standard spec improvement.

At the same time, there is still plenty of room for improvement in actual energy use, especially with plug load reductions. As we innovate in HVAC and drive the fat out of this system, plug loads are becoming the dominant load in many buildings. Fixtures and equipment typically not part of the specification process should be folded into the design process—in particular, IT equipment.  Tenants of Zero Energy + Carbon buildings should not move in their old equipment – move-in is a great time to select the most efficient equipment available – and items like computer monitors have reduced their typical load by 75% over the last decade. Current computers also have the ability for their automatic sleep modes to be set up remotely and uniformly by IT departments – this should become a standard procedure in all offices today. 

Be sure to design and sell the additional beneficial aspects of Zero Energy and Carbon elements.  Everyone, repeat after me: A Zero Energy or Carbon building is a better building and asset, especially when it is actively designed with that in mind. The potential list here is long – tighter envelopes for better health and durability; more thoughtful and effective daylighting and views; thermal comfort; islandable operability; and even beauty. The reality is that as we mainstream Zero Energy + Carbon, we have to be good at selling it to an array of folks. Most people we will engage with will want to do the right thing but will need to find broader reasons as well. 

Futureproofing against the coming climate crisis intervention is a good reason for building Zero Energy + Carbon now. To date, most of the Zero Energy + Carbon market has been established using standard market mechanisms, with a handful of government incentives. I personally believe that sometime this decade, as the climate crisis becomes a more experiential reality (fires, anyone?) we will experience a tipping point where our world finally says enough is enough, and a much more top down governmental intervention around energy and carbon will occur, to a degree that it will make Covid efforts look like small fry. Similar to Covid limitations on building and business operations, it is likely energy hog buildings will be confronted with substantial curtailment of their operations through carbon rationing. Building and retrofitting for top efficiency now futureproofs businesses, organizations, and individuals from this potential.   

Finally – and perhaps most importantly – commit to living a carbon positive life. I realize this doesn’t quite fit the rest of this post, but it is something I’ve been feeling a lot of late. There are so many unknowns in our future, but we CAN take responsibility for our own lives. If we, the climate vanguard, fully reoriented on our living – in our homes, our transportation, our fuel choices, our food choices, our purchasing – it really would make a difference, driving early adoption innovation. Many of us are strong in one or two areas and weaker in others (it’s meat and air travel for me). As corporations like Amazon drive the Climate Pledge in the corporate and organizational sectors, I believe it is incumbent on those of us leading the climate solutions movement to boldly and enthusiastically show what climate positive living looks like.

Learn more about ILFI’s cutting-edge Zero Energy and Zero Carbon programs and hear from industry leaders at the Zero Carbon Conference, online on October 7-8. Find out details and register here.

The following is an excerpt from The Power of Zero: Learning from the World’s Leading Net Zero Energy Buildings by Brad Liljequist, our former Zero Energy Director at the International Living Future Institute. Get 30 percent off The Power of Zero from Ecotone Publishing using the code POZ30. 

The International Living Future Institute defines Net Zero Energy (NZE) as “One hundred percent of the project’s energy needs being supplied by on-site renewable energy on a net annual basis.” In one simple, elegant sentence, a radical agenda for eliminating carbon dioxide emissions and use of combustion fuels within the built environment is set in place. In short: generate what you use. With this crisp idea, an array of powerful forces and concepts are brought to bear on some of our time’s most challenging problems.

Restated in more basic terms, Net Zero Energy buildings and communities generate as much energy as they use over the course of the year. The significant majority of NZE buildings are connected to the grid, with a meter that spins backwards and forwards: when the building is generating more than it uses it builds a surplus, and when it uses more than it generates, it draws from that surplus. At the end of the year, at a minimum it nets to zero use, or potentially is net positive. In practice, NZE buildings have to significantly lower the energy use from typical consumption — usually a 60- 80 percent reduction. On-site energy generation offsets the remaining use.

Net zero energy is such a radical and powerful concept because it is one of the key solutions to carbon neutrality and the elimination of fossil fuel use. If we apply favorite Institute questions of “What is the end game?,” and, “What if everyone did it?” to net zero energy, the end result would be massively positive. By sector, energy use in buildings is the largest single contributor to our carbon footprint — roughly 40 percent, depending on the estimate. If all current buildings were retrofitted to be net zero energy, and all new construction was built to a net zero standard, society’s collective carbon footprint would be reduced by that amount.

The Power of Zero is dedicated to practical, real examples of these buildings in a range of types, sizes, and places which achieve net zero energy usage. The existence of these projects means that net zero energy is a real, viable solution to what is likely the most significant threat to global stability currently in existence, on par with the threat of nuclear proliferation. Remaking our communities to be net zero energy is more than a neat exercise in efficiency. It is a moral imperative to protect those people most impacted by climate change and ocean acidification — those in the developing world and future generations. It eliminates one of the major drivers of military action (acquisition and protection of energy supplies) and degradation of local wilderness in the form of extraction impacts.

Within the framework of the International Living Future Institute’s thinking about human development and living in restorative harmony with the Earth, net zero energy stands as a gateway. Energy in all its forms is a key component of life; living in a way that draws vitality from within, instead of exchanging resources from others without positive return, is the way of nature. To our peril much of historic Western development has ignored this pattern of synergistic exchange, now to our peril. Net zero energy is the first opening into a new way of approaching what we make and dwell in, asking the question: How do our actions add to rather than subtract from energy supplies? Net positive energy, at its heart, is a biomimetic reflection of energy flows within nature.

In less philosophical but more practical, metaphoric terms, net zero energy represents old time, traditional values.

Living within your means

One of the most conservative values is to live in a way that does not exceed what you have. You do not eat your seed corn, and you take responsibility for yourself and family.

Thou shalt not steal

The unfortunate reality is that many of our resources have been obtained through power relationships that exceed a just exchange between the recipients and givers. Perhaps most compellingly, it is clear at this point that we are taking our descendants’ heritage from them, as they will bear the brunt of our irresponsibility in energy use and its impacts.

A penny saved is a penny earned

Our grandparents’ generation knew the value of simply using less. Net zero energy buildings and communities squeeze out every watt of savings possible. These buildings are not just resilient in their interaction with the Earth, but also in their long term basic demands of operating costs, providing an essentially conservative financial platform of living.

Reap the harvest

A foundational concept of human civilization is that we organize and systematize the gathering of the fruits of the Earth. For millennia that idea has primarily referred to a harvest of food. With new technologies and paradigms, it also can mean harvesting the energy provided by the Earth — the sun, wind (really solar energy), and tides.

Mottainai

Derived from an old Shinto concept that material objects have souls, this Japanese word embodies meanings of both wastefulness and irreverence. More recently, Kenyan Nobel Peace Prize winner Wangari Matthai sought to popularize the term internationally as a way to place a sense of the sacred on our thoughtful use of resources.

Net zero energy is also a very compelling concept to the general public, which crystalizes core needs of dramatic energy reduction and renewable energy generation into one simple, easy-to-understand idea. While it can be very challenging to excite the average person about the sometimes arcane world of energy efficiency, net zero energy has a demonstrated ability to inspire and involve people. NZE brings forward a can-do spirit which combines the best of applied technology and design, Buck Rogers, and big jumps forward. It is also an accessible, inspiring response to people beleaguered by a sense of hopelessness around larger energy use and climate problems.

Net zero energy buildings represent the beginning of a new era of innovation within the world of buildings. Amazingly, homes in much of the world are still built the way they were one hundred years ago. Within North America, balloon framing pioneered in the 1800s is still the standard. It is as if we still drove Ford Model T’s instead of electric vehicles, or used mechanical adding machines instead of computers. In most other sectors, the performance characteristics of the desired object tend to drive technological development, while in the building sector, the technologies have tended to define the design. We hopefully stand at the beginning of a new era of building design evolution, which reflects a whole array of human and environmental needs, only one of which includes eliminating the energy footprint of the built environment.

A key component of innovation to achieve net zero energy performance is a deep drive towards designing with nature, the laws of physics, and biomimetics. Net zero energy buildings take advantage of diurnal temperature swings, and available naturally stored thermal energy, capturing and retaining what is needed to serve the building. The gift of the sun, from which all life springs, is fully embraced, through daylight, heat, wind, and photons. Many of the key technologies used in net zero energy buildings respond to natural phenomena, such as evaporative cooling, stack effect, the ideal gas law, and gas/liquid/solid phase changes. Some of these phenomena are described in more detail in section three, below.

As part of its net zero and net positive energy requirements, the Institute prohibits the use of on-site combustion. There are a number of reasons for this prohibition. Typically, building related combustion involves so-called “natural” gas, which adds CO2 to the atmosphere and oceans. Eliminating its use is a major priority of the ILFI. Extensive use of woody biomass removes critical material from natural cycles, and in many cases accelerates climate change by speeding up the slower release of CO2 through decay. Biogas supplies can prove transitory, and easily default to natural gas. Depending on the type of combustion, local air quality impacts can be significant. While it is recognized that most net zero energy buildings are connected to a grid which is reliant on the larger energy grid, of which natural gas and coal burning power plants currently play a significant role, the Institute’s end goal is a fully renewable energy grid which includes the complete elimination of combustion, particularly of fossil fuels. Impacts of combustion are discussed further in the section below, and the end state vision of the grid is discussed in Part IV.

Finally, in 2013, the Institute launched the Net Positive conference in San Francisco, California, indicating a conceptual shift in net zero energy. Version 3.0 of the Living Building Challenge evolved the Energy Petal to require 105 percent of a building’s energy use to be offset by on-site generation, rather than 100 percent. At the same time, the Institute has strengthened and extended its Net Zero Energy Building certification. In terms of actual change in energy generation, the amounts are relatively modest. In concept, however, the evolution of net zero to net positive is significant: nature does not do zero. Natural systems tend to be fecund and generous, providing a bounty beyond what the individual needs. Net positive energy is a libation of abundance, a ray of goodwill and intention to our neighbors and the future.

One of my all-time favorite tools is the Kill-a-Watt meter.  Available in several models, this inexpensive, handy tool allows you to find out how much electricity a given plug-in item uses.  Simply plug it into the wall, then plug the item into the Kill-a-Watt.  Several different settings provide real-time wattage, voltage, and amperage readings, as well as watt-hours to determine usage over time.  The meter is very handy for determining how much equipment uses on standby, as well as when fully on.  Many things still draw energy even when fully “off”.  I have to admit that more than once I’ve been taken aback by the amount a beloved piece of equipment uses on (my 1940’s electric GE clock draws 24 watts 24/7 – it sure is nice, but that amounts to 210 kilowatt hours a year – the equivalent of the output of about ¾’s of one of our solar panels – not a trade-off we’re willing to make).

My beloved niece recently told me she was doing a science project about her high school’s energy use and ways to reduce it (I swear, I had no influence on this choice).  I simply handed her my Kill-a-Watt meter and suggested it might help.  Check out the chart in the lower middle of her display – a fairly nice little analysis of standby and on watt and kilowatt hours by electrical item. Anyone need a great, fun energy professional in six or seven years?

Get a Kill-a-Watt meter, find your worst offenders, and get rid of them!

ILFI is excited to announce its new Zero Carbon Certification.  Providing a new performance pathway situated between Reveal and the Zero Energy Certification, the Zero Carbon Certification provides greater flexibility around project fuel types (for existing projects) and placement and ownership of offsetting renewables.

The ILFI Zero Carbon Certification is the first worldwide Zero Carbon third-party certified standard.  It recognizes the growing interest and focus on a broad-based tool for highlighting highly efficient buildings which offset their energy use, regardless of location of renewables, as well as accommodating previously built combustion based infrastructure.  It also recognizes increasing corporate efforts to create meaningful carbon offsetting systems which result in real, positive change.  It builds on and implements the Zero Carbon concept released by Architecture 2030, the Rocky Mountain Institute, and the New Buildings Institute in 2016, and the worldwide call for zero carbon standards from the World Green Building Council issued in 2017.

Summary of Zero Carbon Certification requirements

During a one-year performance period, buildings must achieve a targeted energy efficiency level.  Existing projects may use any type of energy, including those that are combustion based, but new projects may not include combustion.  One hundred percent of the project’s energy use must be offset by on- or off-site renewable energy on a net annual basis.  The project must provide offsetting renewables which have the equivalent of 15 years of project power, provide additionality, and have durable ownership integrity associated with the project.  The complete requirements can be seen here.

How does Zero Carbon relate to Living Buildings, the Energy Petal, Zero Energy, and Reveal?

In the hierarchy of quality and sustainability, the Zero Carbon certification is the first step towards Living Building Challenge certification.  It represents a significant improvement over the norm, and fills in a gap between Zero Energy Certification and the energy performance of code-based buildings or less stringent green building certifications. The following chart shows the hierarchy and associated attributes of ILFI’s Energy certification levels:

Features

• Has worldwide applicability; can be used broadly by projects, corporations, districts, and jurisdictions seeking to substantially raise the bar on efficiency, and create a renewably powered electrical grid.
• Useful for existing buildings which have combustion embedded within their existing mechanical systems, and where there may be constraints on higher levels of efficiency improvements, where a full renovation is infeasible.
• Provides a broad range of efficiency targets, including where zero carbon levels have been locally established.

Visit the Zero Carbon webpage to learn more about our newest certification!

My first introduction to mineral wool was during a 2005 visit to the pioneering Zero Energy project, BedZED, in England. There were a lot of amazing things to take in that day, and mineral wool was one of them. Insulation made out of rocks? Cool! To find out that it was the predominant insulation in Europe was equally surprising, especially coming from the United States, where fiberglass insulation was (and is) the norm (note that in North America, mineral wool refers to insulation made of stone and slag; in Europe, it also refers to fiberglass insulation.  Here I am using the North American definition).

I have become a fan of mineral wool insulation. It is made by spinning molten rock (lava) into fibres, and applying a small amount of organic binding material. Its R value is on par with most other insulation types. It comes in various forms, including a semi-rigid board that lends itself well to exterior mounted insulation. It has a high melting point, making it fire resistive. It is also excellent for soundproofing. It doesn’t use petroleum as an ingredient, as does foam. It is also durable.

I think where mineral wool particularly shines is in exterior applications of semi-rigid board, outside the structural shear wall or weather-resistive barrier. This is the approach taken at the Bullitt Center and many other Living Buildings, as well as Passive House-certified buildings. Unlike foam, the semi-rigid mineral wool board is fully breathable, meaning that water that gets behind it can get out easily, reducing concerns about the dew point and condensation. At the horrifying Grenfell fire in England—where polyisocyanurate foam insulation was retrofit on the tower’s exterior behind an aluminum rainscreen—the insulation provided fuel for the fire to spread rapidly up the building. Comparatively, mineral wool has a much higher fire resistance.

One issue with mineral wool has been that it typically includes phenolic formaldyhyde as a binding agent. Although more benign than urea formaldyhyde, phenolic formaldyhyde is still a Red List ingredient. While ILFI allows use of phenolic formaldyhyde-based mineral wool outside the building’s air barrier for Materials Petal compliance (recognizing its other excellent qualities), it has not allowed it inside the envelope. Rockwool (previously Ruxol, Inc.), the world’s largest mineral wool manufacturer, has recently released a formaldyhyde-free mineral wool product for interior applications, which uses corn syrup as a binder.  According to Doug Eichler, Technical Solutions Manager for Rockwool, ideal applications for Rockwool AFB Evo^TM are “Interior wall and floor applications that require acoustic and fire rated performance.”  He also added that the product is water repellant.  ILFI appreciates Rockwool’s market leadership in evolving this product to be Red List-free.

Rockwool is not the only manufacturer to provide transparency through the Declare label; in fact, Owens Corning also provides a product through their Thermafiber Brand.

Furthermore, leadership has been provided by Owens Corning, Knauf, Amorim Isolamentos, SA, Carlisle Syntec, Autex Industries LTD., Ecovative, and GAF, which all have insulation products with transparency through Declare. Owens Corning also has the very first Certified Living Product. In the coming months, we will be profiling more energy-related products that have cross germinated through the ILFI network.

Brad Liljequist: Hi David—tell us about yourself.

David Mead: I’m a Building Performance Specialist at PAE Engineers. I work as both an energy engineer and architect within our office, integrating systems to achieve high performance goals for projects. I went to school for architecture originally, and I kept wanting to focus on performance, and realized building systems were the key to improve performance. I’m functionally a mechanical/energy engineer on a daily basis now, making sure all the pieces are integrated.

BL: A very important role indeed! So you were a Project Drawdown Fellow—what is Project Drawdown?

DM: Project Drawdown was created by Paul Hawken. I understand he created it after reading the seminal article several years ago in Rolling Stone by Bill McKibben, addressing just how challenging the climate change numbers are looking.

Paul was concerned that the sustainability movement had a strong doomsday narrative, and that the language people were using was self-defeating. The whole idea of Project Drawdown was to say, “Okay. Let’s look at the solutions,” because everybody had been looking at what the problems were. He also wanted a holistic look at what solutions could be. He put a call out to researchers all over the world, to see if people would be interested in helping with this—and they got an amazing response.

BL: It’s interesting how influential Paul Hawken has been for so many of us at different points along the last couple decades. He’s a very important person in our movement. So how and why did you get involved in Project Drawdown?

DM: I saw an online post about Project Drawdown. I read the premise and thought it was brilliant, because of its solutions focus. It matched what we do in our industry, and what I do on a daily basis. I personally know there are a ton of solutions, and that we can effectively address climate change. So I offered for PAE Engineering to be advisors on the project, which we did, and then a few months later, I actually got an email from Paul, asking if I would be interested in doing the Net Zero buildings fellowship.

BL: Project Drawdown identified about 100 tangible climate solutions—what were some of the most compelling things that you learned being part of it?

DM: Within the realm of normalizing zero energy buildings, it’s clear that we are just at the very beginning of its growth—it’s behind the overall market uptake of solar energy generally. But the critical thing we learned was that if you look at the numbers, it is clear that zero energy has to target existing buildings and retrofits—we simply won’t reach our numbers if we don’t.

BL: I totally agree. I was at the American Geophysical Union building in Washington, DC, a couple weeks ago, an existing five-story building that they are retrofitting to be zero energy. They’re doing it in a cost-effective, thoughtful, pragmatic way. We have to take advantage of major renovations as they happen.

DM: Right. Another big surprise was the refrigerant management impacts—refrigerants have a high global warming potential and the majority leak into the atmosphere out of HVAC equipment and appliances. I’ve always known that’s an issue, and we have talked about it within our firm quite a bit. But to see it be the number one solution in Project Drawdown is really concerning. In some cases, it can completely offset whatever emissions savings you’ll have from energy efficiency.

BL: It’s a huge issue, and we’ve been talking about it a lot too at the Institute. I think that we want to tackle this as soon as we can. The revisions to the Montreal protocol were great, but they’re also slow. So what are the alternatives?

DM: One is to take a super passive, envelope driven approach using electric resistance. The Rocky Mountain Institute Innovation Center took this approach in climate zone seven, which is unheard of.

BL: It’s amazing.

DM: Yeah, it’s so cold there. But that approach works best in cold, sunny climates—it’s harder in humid climates.

There are also natural refrigerants, that been used since the 19th century actually—CO2 and ammonia—and these are coming to be used more again. The problem is that they both have engineering challenges. CO2 is good for heating, not very good for cooling, and ammonia has its own challenges.

There are also natural refrigerants, that been used since the 19th century actually—CO₂ and ammonia—and these are coming to be used more again. The problem is that they both have engineering challenges. CO₂ is good for heating, not very good for cooling, and ammonia has its own challenges.

BL: The CO₂ heat pumps have a temperature range that is challenging in some cases, right? But also very advantageous in others. I’ve been super impressed by the Sanden CO₂ heat pumps, as well as the larger ones by Mayekawa and others.

DM: There are new refrigerants coming out known as A2L refrigerants, but they’re mildly flammable. This is a potential issue if it’s being pumped around a building with refrigerant lines, like in a split or VRF system. So we’ll see where that lands but it is likely most of the market will move to those newer refrigerants.

BL: You were talking a little bit about where we are in the growth trajectory with zero energy. What we see is that the growth of zero energy buildings is exponential—not aggressively so, but the trend is real. In the last couple of months, we’ve averaged nearly three projects registering a week, during what is normally a quiet time of the year—certainly the fastest rate we’ve ever seen.

DM: That’s great.

BL: So what do you think it’s going to take to make zero energy the new normal?

DM: I think a lot of society doesn’t know it’s possible. It’s not part of our cultural narrative. We have to show the broader culture that we can truly address climate change. We just need more examples, both at the high end and in everyday vernacular architecture, in more locations. And then we need to be sure people know about them—many people in Seattle still don’t know about the Bullitt Center.

I think the other thing is getting serious about putting financial resources into the solutions. If you took the top ten Project Drawdown solutions, it seems quite prohibitive, like billions and billions of dollars. But from a societal standpoint, it seems easy. I wondered if you just took the hundred richest people in the world and you just looked at how much they’re worth. Could they actually implement these solutions? The answer, at a high level, is yes—a hundred people have more than enough money to pay for the top ten solutions which would help 7.6 billion people. We live in unusual times, right? Wealth is so concentrated.

BL: Just to put another cut on it… something I talked about in The Power of Zero is that the United States spent 7.2 trillion dollars in military spending in the Middle East since the 70’s—that equals $59,000 dollars per American household. Which ironically is about the same cost it would be to retrofit every house in the US to be zero energy. Whether it’s coming from above or below, it feels like we can do it, but it is going to have to be that scale of intervention too.

DM: Yep.

BL: If you got to be king for a day or Bill Gates, what would you do to make zero energy buildings the norm?

DM: I think, I would challenge all the leaders of the world to start talking about solutions and stop focusing on short-term profits. Like short-term, even in your own lifetime. I always like ideas such as we’re borrowing this planet from our grandchildren. Also, there’s the carrot versus the stick. We’ve incentivized elements of zero energy, and the adoption rate tends to be really small. Whereas, if it’s code, the adoption rate tends to be a lot higher—pretty much 100%.

BL: My philosophy is that you use incentives and inspiration and all those things to get to a couple percent of the market adoption zero energy. Enough that you get your examples, you get your inspiration, you get your knowledge base going, and then it needs to be codified. Given the scale of the problem right now, it seems like that’s what we have to do.

DM: It is sad to me the narrative around climate has become so entrenched and politicized. We need a better dialogue and better solutions to try to get everybody onboard. I think Project Drawdown is a great example of that, where it gets people across lots of spectrums to see that there are solutions. It’s not a political debate; it’s based on science and physics.

BL: It’s really about risk management at the end of the day.

DM: Another area that was highlighted in Drawdown was food production. That is actually where they saw the most emission savings—there is so much waste in food production, which is really fascinating. Growing food in your yard, limited meat consumption, using ugly produce, are all very important. Everybody who reads this should go plant a garden and try to grow as much food as they can in their yard. Try to be as resilient and self-sufficient as possible. And a lot of that fits in the conservative, self-sufficient approach.

BL: Any final thoughts?

DM: I’m still hopeful, and I think that’s the key takeaway of Drawdown. Stay focused on the solutions—let’s get this done!

Last week, I was in the District of Columbia, hosting a zero energy seminar and reception as part of our Zero Energy Roadshow partnership with Arup.  While I was there, I was able to check in on the construction progress of one of my favorite ZE projects—the American Geophysical Union Headquarters, which is a ILFI registered Zero Energy project.  This project is a retrofit of an existing five-story office building—really pushing the envelope of what is feasible to achieve with zero energy.  It is about halfway complete.

Matthew Boyd, Building Services Manager for the American Geophysical Union, and Greta Perry, Vice President of MGAC and owner’s representative for the project, kindly gave me a behind the scenes tour of the project.  I have been working with Matthew, Greta, Hickok Cole Architects, and Interface Engineering for a couple of years now on zero energy elements of the project.

One highly innovative part of the project is that it will use sewage heat recovery for a pre-warming system for the building’s heat pumps.  This system operates akin to a ground source heat pump—sewage is diverted from the adjacent sewer main into a mechanized holding system, where the latent heat in the waste stream provides a thermal base for the heat pumps to then lift to full temperature (on average, sewage temperatures are quite warm—often well into the 60s Fahrenheit—think about the cumulative thermal energy of thousands of hot showers!).

Remarkably, the sewage trunk adjacent to the site was built in the 1890s and is still fully in use.  Serendipitously, the pipe had been cut and opened the day before my arrival, giving me a chance to check the main out.  To maintain the main’s structural integrity, the Skanska construction team had shotcrete the interior of the pipe.  After the shotcrete had dried, the entire assembly was sawcut, and the opening lifted out intact.  It was really cool to see a piece of historic infrastructure being reconfigured to be maximally efficient.

It is incredibly exciting to see the project underway.  The ILFI has been working with the District government for a number of years now on zero energy innovations—through the 2014 Net Zero and Living Building Financial Study, prepared jointly with New Buildings Institute and Skanska; a series of zero energy events and charrettes in 2015; and finally the Clean Energy DC Plan, prepared in conjunction with Integral Group and the Institute for Market Transformation.  The idea of sewage heat recovery was discussed in some of the 2015 zero energy charrettes—it is exciting to see people, ideas, and momentum growing into real, tangible projects, which will, in turn, impact the broader understanding of climate solutions in the US capitol.

ILFI has recently been working much more with the Passive House community, to connect the networks in both people and thought. This fall, we had an excellent Net Positive Symposium in Vancouver, held jointly with Passive House Canada, as well as a Net Positive track and class at the North America Passive House Network conference in Oakland, CA.

A key element of zero energy and passive house construction is a tight, well-insulated envelope. One product that helps achieve airtight envelopes is the Declare labeled Proclima Vana and Profil tapes. These tapes are made for an array of applications, such as taping seams of plywood to create a continuous air barrier or joining air or WRB membranes.

John Druelinger of 475 High Performance Building Supply shared the following about the Proclima tapes:

“Tescon Vana and Tescon Profil were designed by Pro Clima for building airtight, efficient, mold-resistant building assemblies. Vana is recommended for taping flat seams, while Profil’s 3-split release backing helps for taping corners, such as window frames. They are each made of durable, fleece-backed materials and utilize solid, pressure-activated, acrylic adhesive that has been third-party advance-age tested to provide 100 years of adhesion. Both Vana and Profil are suitable for interior and exterior application, are water-proof yet vapor-open, capable of 6 months UV exposure, and work without a primer on most sheathing materials. A primer is recommended only in situations where the surface being taped is very rough or porous.”

The icing on the cake is that these tapes are Declare labeled and Red List free. We have nearly 1500 labeled products today—with more added nearly every day—and an array of these are in the energy efficiency space.

Proclima products are imported into the United States by 475 High Performance Building Supply, based in Brooklyn, NY, with distribution centers on both coasts. 475 is a great knowledge resource—they have a ton of great information about detailing and installation on their website, and are available on the phone for specific technical help on applications.

For the past three years, we’ve hosted the Net Positive Energy and Water Conference to explore net positive energy and water solutions. We’ve recently evolved the Net Positive event model to provide even more bang for our energy buck. To build on the metaphor, we are trying to provide capacity building and education to our current and new constituents more efficiently and cost effectively.

We are partnering with aligned organizations to host well curated content that spotlights specific topics and issues, sometimes with a regional focus. We will host the events in venues that have strong value alignment with us, such as universities with interest in Living Future programs, or retreat centers with a natural or biophilic focus.

We are particularly excited about the first of our new Net Positive events. The Net Positive Symposium, at the University of British Columbia – Robson Square in downtown Vancouver on October 30, is being jointly presented with Passive House Canada. This single day, regionally focused event will investigate the synergies between Passive House, Living Buildings, and Zero Energy through fast moving vignettes and case studies. Check out more details here.

Additionally, we’re partnering with the North America Passive House Network to provide a Net Positive track at their conference, in Oakland October 6 and 7, as well as providing a half day class on the basics of the Living Building Challenge. Find out more here.

There are many inherent benefits of a Passive House design approach, including cost effectiveness, ability to scale, resiliency of the building during power outages, and internal temperature stability, allowing mechanical heating and cooling to coincide with renewable production peaks. We look forward to investigating these topics as we move forward together.

Working more with the Passive House community and framework is just one of many new partnership angles our Zero Energy program is introducing to the Living Future community. Stay tuned for more exciting Net Positive events and symposia planned for 2018!

I first become interested in zero energy buildings in 2003. There were several things that pulled me into the concept, and probably the most compelling aspect was the scale of the change. At the time, I was managing a municipal green building program and we were struggling to convince developers to make relatively minor incremental changes like using low-e windows or high efficiency furnaces. The notion of zero energy was such a radical leap forward. The other big thing that was intriguing to me, let’s face it, was that it was cool.

Zero energy as an aspiration, on-the-ground reality, and climate solution movement is at an interesting point in its history. Zero energy is all the rage, with many more organizations and events actively addressing it as a topic. Many utilities are starting to look into a likely future of much higher efficiency buildings with integrated photovoltaics, and are trying to figure out the ramifications of shrinking base loads and peaking generation when the sun is out. Even though at this point we only have 43 certified projects, things are clearly taking the next scale step up—we are nearing 400 registered projects. From our unique position of engaging with many high-profile players and projects in feasibility, we are able to see zero energy taking the next big step.

As zero energy becomes more mainstream, it is a great time to step back and think about what role zero energy has taken to date, which informs its value proposition moving forward. Here are seven observations I’ve learned since zero energy buildings first piqued my interest nearly 15 years ago.

Zero Energy is a Key Element of an Integrated Philosophy of Design

When zero energy was integrated into the Living Building Challenge in 2007, another design perspective was introduced. Buildings are like flowers, receiving all the energy they need from the sun, sharing energy in a reciprocal relationship with their biotic community, and operating at the far reaches of efficiency. Zero energy was not just cool, it reflected a higher, deeper system of design thinking fundamentally based on nature and biomimetics.

Zero Energy Brings People Together

In today’s complex times, perhaps the most compelling aspect of zero energy is represented by what I witnessed during the zHome open houses in 2012. I had directed development of this groundbreaking project, the first multifamily zero energy project in the United States. The team did a thorough job planning and marketing tours of the project, held over nine weekends. We ended up having 10,000 people visit the project for two, deep dive tours of the project. It wasn’t the numbers, though, that I found most compelling. It was the diversity of backgrounds. Yes, we had many NPR-listening, Seattle-dwelling urbanites make the trek out to the suburbs, but we also had just as many average folks. Perhaps the most gratifying crowd was the large numbers of visitors from east of the Cascades, the “red” part of the state. Zero energy brings together many threads: climate solutions, practicality, gee-whiz, can-do, high-tech, that transcend the typical narrative of today.

Zero Energy Drives Efficiency

So what else is zero energy good for? A lot more, actually.

Zero energy buildings provide a couple key self-limiting mechanisms to drive efficiency. These elements force buildings to reduce their Energy Use Intensity (EUI) to match the available renewable generation on site. Similarly, zero energy buildings have a self-reinforcing financial mechanism for efficient systems. A more efficient building results in the need for fewer renewables, which have substantial cost. While it is true that in the past, higher solar costs really reinforced this financial container—essentially almost anything you could dream up on the efficiency side would be less expensive per watt saved than renewable generation. But even at lower renewable prices, it still reinforces scouring the alternatives for efficiency gains.

Zero Energy Connects the Building and Occupant

Another powerful aspect of zero energy is that it tunes users into the energy performance of the buildings in which they live and work. In zero energy buildings, systems are so efficient that typically, the single largest loads are from the users. Zero energy performance rests in the hands of the occupant, which is perhaps more effective than any other strategy to reduce their usage. Related to this is zero energy’s reinforcement of self-identification with next-generation energy systems. Hosting a small power plant on your roof connects users with energy in a way that a power line does not.

Zero Energy Makes the Grid More Efficient

Zero energy buildings (ZEB) also place energy production at the point of use, meaning there is no line loss (at least when the ZEB is using the onsite production, but typically ZEB projects are in urban settings, where excess generation is used just offsite). The average line loss within the United States, for example, is 5%. That is a lot!

Zero Energy is Space Efficient

Roof-mounted offsetting solar also has lower impact on the environment that many larger utility scale renewables, which may form their own monoculture, especially when the installation sites are graded, graveled, and fenced. Roof space is an often underutilized asset, and zero energy buildings turn that into valuable space.

Zero Energy Supports Local Economies  and Stable Investment

Purchasing of building mounted renewable energy also supports the local economy. The majority of solar industry jobs are in installation, meaning zero energy buildings provide additional skilled labor jobs. Finally, for many people, real estate assets form the core, conservative component of their investment portfolio. Improving the quality of those assets by making them lower cost in operation, higher quality, and more durable, all reinforce their investment profile and benefit.

Recently, the International Living Future Institute released a new limited exception allowing renewables to be placed off-site, for tenant improvements, areas with grid constraints, and high-energy intensity/high density uses. In crafting the conditions under which this exception could be used, we drew from many of these beneficial elements of zero energy, seeking to rebuild it conceptually in albeit a deconstructed fashion.

In this era of climate obfuscation, tangible, positive climate solutions are critical. While zero energy buildings and communities don’t get us all the way to the energy end game (I’ll save that discussion for later), they are a really big part of it. We’re grateful to be one of the key zero energy leaders worldwide, and look forward to resolving the fossil fuel conundrum together.

Editor’s Note: The following excerpt is a chapter from the Power of Zero, the latest release from Ecotone Publishing.

Net Zero Energy — the first stage in a transformation toward a carbon-free future.

Net zero energy (NZE) buildings, though compelling and meaningful, are just a beginning. We are only in the earliest days of a revolution in net zero energy design and technology. The energy use intensity (EUI) of net zero energy buildings will continue to drop, the efficiency and output of renewable resources will increase, and the cost of design, construction and operation will decrease, making net zero energy projects more common. New net zero energy design ideas and technologies will evolve, and enable new pathways for achieving this vital concept. It is critical to understand, however, that net zero energy buildings, and even net zero energy communities, do not eliminate fossil fuel usage. Net zero energy buildings are not a universal solution—they are just a component. In order to free ourselves from fossil fuels, we need a deeply integrated revolution in buildings, transportation, and the power grid.

So what advancements are on the horizon?

Net Zero Energy Building and Designs — The Next Generation

The boundaries of passive and active systems blur

As knowledge of net zero design spreads, the duality between “passive” and “active” approaches is fading. Net zero energy buildings are partially built on the heritage of passive solar buildings of the 1970s, which—at least from a heating and cooling standpoint—relied on simple thermal gain and storage. As the net zero revolution began, sophisticated technologies—for example, heat pumps and LED lighting—dominated the discussion.

Today, however, the best net zero energy buildings seamlessly combine both passive and active design concepts. In fact, it is becoming increasingly difficult to describe net zero energy buildings in those terms. For example, the Bullitt Center utilizes a highly sophisticated software program. Using real-time weather data to open and close windows depending on wind direction, the building is naturally cooled and ventilated based on thermal comfort needs. Windows also allow passive solar gain, but only during cooler months, and only if the computerized system opens the exterior shades. The passive solar gain typically contributes to only a portion of the building’s heat, which is supplemented by the heat pump system. Are these systems active or passive? Because they are thoughtfully designed with an attention to naturally occurring assets, these systems uproot traditional categorization. Moving into the future, sensitively designed systems that take maximum advantage of nature’s gifts will become the norm.

Micro heat pumps

The revolution in heat pump technology will continue, with a new focus on micro systems. Such systems allow appropriate load matching for buildings with excellent thermal envelopes that have low heating and cooling demand. Sanden, a major automobile heat pump and air conditioner manufacturer, recently entered the building market, suggesting a renewed interest in this sector.

Elimination of high-GWP compression gases from heat pumps

Today, high global warming-potential compression gases, such as hydrofluorocarbons (HFCs), are used in heat pumps. These substances have the potential to leak, creating an additional impact on the climate. The shift from combustion- to heat pump-based heating systems must be accompanied by a shift to CO2 as the primary compression gas for heat pumps, lest we simply replace one problematic gas for another. Thankfully, this shift away from global warming-causing compression gases has begun.

High-performance windows become the norm

Windows that are typically used in net zero energy buildings, with U-values in the 0.20s, are fairly custom, though they have high price tags. However, as glazing and window technology matures, and especially as jurisdictions begin to codify lower U-values for the purpose of energy management, these windows will become much more prevalent, similar to the switchover to low-E glass that happened a decade ago.

Dedicated focus on high energy use sectors

Certain very high EUI building types—hospitals, restaurants, factories, data centers, and supermarkets in particular—lag behind other sectors in the adoption of innovative technologies. These commercial buildings use vastly more energy per square foot than primary buildings like homes and offices. The energy modeling for one potential net zero energy building found that heat from refrigerators to went outdoors, instead of using it resourcefully for internal heating. In restaurants, stoves are often run at one hundred percent despite the actual need, and the heat pump revolution has yet to arrive to kitchen equipment. Technologies such as CO2 heat pumps, which produce much higher-temperature water than conventional heat pumps, suggest that new approaches are on the horizon.

Revolution in retrofit technologies

Shy of a complete building overhaul, it can be challenging to deeply retrofit a building for very low energy use. However, strides are being made to streamline the retrofit process and reduce costs. Thermal imaging cameras, a critical tool in understanding building heat and cold leakage, are now radically cheaper, and soon should become a standard toolbox item. Heat recovery ventilators, an obscure and rarely seen item in the past, are now available readily available and significantly cheaper than before. Further,the introduction of vacuum insulation panels, from manufacturers such as Panasonic, offer extremely high R-values per inch.

Revolution in building-mounted renewables

The cost of solar panels has been dropping significantly, suggesting a maturing of the technology, and other elements of solar installation are coming to the fore as the technology becomes more commonplace. Better integration of solar applications during the design process, particularly to facilitate mounting, will bring solar costs down even further. At the same time, panel efficiency continues to increase—just several years ago, 15 percent was standard. Today, twenty percent is now available in the marketplace, while 40 percent has been achieved in laboratory conditions. These performance improvements may seem small, but improvements average about five percent each year, which is quite significant over time.

A much deeper revolution in solar generation is brewing with thin-film, omnidirectional solar cells. Ideally these will absorb the sun’s energy with less regard for solar angle, and will be installed as a wrapped skin, perhaps in lieu of paint. This technology will transform building energy generation again, with much higher levels of building production because panels can be placed in a much broader array of locations, including walls.

Revolution in energy storage

Finally, Tesla and the automotive sector are leading an ongoing transformation in electrical storage. This technology brings us back to the roots of net zero buildings—the off-the-grid passive buildings of the 1970s. This technology could significantly decrease the electric grid as individual buildings become more autonomous in their use and production of energy.