Transforming Building Systems

­­Our 2017 Conference, It’s Electrifying: Exploring NYC’s Climate Plan to Electrify Buildings, was held on October 4. This blog post recaps session two, Transforming Building Systems. Read about session one, Electrifying the Building Industry, here and click here to learn more about the event.

If we can green the grid and make electrification a real possibility, how would this transformation play out at the individual building level? Which technologies will become more pervasive as building systems are converted to electricity? The second session, moderated by Scott Frank of JB&B, attempted to answer these questions.


We won’t get to 80x50 if we continue to rely exclusively on fossil fuels to heat our buildings. Most tenants do not pay for their heat, nor do they have control over it, resulting in an overabundance of overheated buildings, with open windows in the dead of winter (that New Yorkers control heat in NYC apartments by simply opening the windows was confirmed by the knowing laughter throughout the audience).

Marc Zuluaga of Steven Winter Associates introduced himself and dryly remarked that the silver lining of global warming is that less heating will be needed. He gave a crash course on air source heat pumps, explaining the pros and cons of conventional and mini splits, variable refrigerant flow (VRF) systems and air to water heat pumps for domestic hot water (DHW). He pointed out that even with today’s grid, a well-executed heat pump will save carbon relative to a gas-fueled system.

Zuluaga shared common-sense approaches (documented by the Northeast Energy Efficiency Partnership) to getting the most out of heat pumps, and also advocated for addressing the behavioral elephant in the room: a lack of motivation. Unlike the rest of the country, most NYC residents do not directly pay for heat—the cost is baked into our high rents-- and therefore don’t have an incentive to reduce their costs or carbon footprint through conservation. Zuluaga then discussed applications for heat pumps that utilize C02 as a refrigerant. This last point is critical considering the immense global warming potential of conventional refrigerants. Zuluaga asserted that we can’t get to 80x50 without proving out scalable approaches to heat pump retrofits and we also can’t get there without figuring out how to get the most out of buildings that stay on fuel. The crucial next steps will be to pilot a variety of approaches in different types of buildings to provide the market with multiple viable paths to achieving deep carbon reductions.

Moderator Scott Frank noted that retrofitting the existing multifamily building stock is not as glamorous as building new passive house skyscrapers, but it must be a large piece of the climate strategy pie.


For decades, before energy storage was widely available, and renewable energy was fighting an uphill battle into the grid, energy efficiency was the dominant “no regrets” strategy. The traditional thinking was that energy efficiency is a positive and cost-effective goal to pursue, so we should focus on it first and get to the more difficult strategies later. Conferences like this reflect a new perspective–that the electrification and cleaning of the grid can happen alongside energy efficiency.

And, indeed, there is still work to be done when it comes to efficiency: Developer Steve Bluestone of Passive Dwellings fervently advocated for the importance of building envelope performance, saying, “If you don’t do the envelope right, don’t even bother with an energy-efficient heat pump.”

Citing examples of his passive house construction in NYC, Bluestone described the need for economic incentives to spur envelope efficiency.


Closing out the presentations, John Cerveny of NY-BEST explained the big trends in energy generation and storage—and what they could mean for buildings. The variability of renewables is a real challenge for the grid. As Frank explained, wind peaks at night with a bias toward the winter and solar peaks during the summer. While our grid is currently constrained in the summer, but not in the winter, electrification is expected to change that.

This means anything that can smooth peak energy demand will likely be a necessary tool in future energy infrastructure. The cost of batteries has decreased and, respectively, their application has increased—although not without some hiccups. Their size, capacity and safety still pose real challenges to widespread adoption, especially when used indoors—but Cerveny seemed confident these are obstacles we can overcome.


As Urban Green’s Ellen Honigstock promised at the beginning of the day, we left the conference with many more questions than we did answers. Heat pumps for space heating and hot water, efficient building envelopes and energy storage technologies have come a long way. This technology will likely become more widespread as we work toward 80x50 and building systems convert to electricity.

We’re now examining the critical challenges that building systems will need to overcome for electrification to become a reality. This conversation will continue on December 7th at It’s Electrifying: Converting Heating Systems and on February 6th at The Future of Domestic Hot Water. Attendees will learn the latest thinking on heat pump technology and explore the opportunities and challenges for new and existing buildings.


About the authors

Rebecca Elzinga
Rebecca is the Education Development Coordinator at Urban Green.