2021 Webinar Series - 17 Electrifying NEW Construction
Electrifying NEW Construction: Commercial & Multi-Family Focus
New construction presents an ideal opportunity to get it right the first time! While not yet a hard requirement, avoiding fossil fuels in favor of electric heat pumps can be done today with a little creativity. This session will highlight two projects that use a combination of innovative design, maximizing incentives and the right financing to achieve zero emissions buildings. Plus we’ll hear about NYSERDA’s New Construction program with available technical and financial support, which can complement the NYS Clean Heat incentives for commercial construction across New York State.
Matt Brown / NYSERDA
Jens Ponikau / Buffalo Geothermal
Tony Amis / Endurant Energy
- What is a NYSERDA channel partner?
- A channel partner is an organization that we partner with to hold conferences, panel presentations, and share information back to the market. They are generally associations of professionals, but can be several different types of organizations.
- Please describe carbon neutral ready in more detail
- A carbon neutral ready building is a highly efficient, all electric building or home. There are exemptions for emergency generation and industrial/process loads. Additionally, they should take into account resiliency, health, comfort, functionality and minimize embodied carbon and use low Greenhouse Warming Potential refrigerants.
- Do you think the higher ground temps at Greenwich are typical in heavily urban areas? How does it compare with other similar projects?
- Yes - it demonstrates the urban heat island effect
- Tony, how good is the conductivity between HDPE loops in pile concrete compared to standard grout in a typical bore hole?
- The conductivity test was run for 96 hours to ensure we got a true representation of the conductivity value due to the larger diameter of the pile compared to a borehole. The grout used in the piles had a high sand content and conductivity value was not too dissimilar to borehole grout.
- If Tony had access to the street and sidewalks surrounding the Greenwich building for loops would you have been able to do the whole building load with geothermal as opposed to combining gshp and ashp?
- Probably - However there were a lot of services in the sidewalk plus being outside of the site boundary would have created a regulatory and legal challenge from the Developer - Nothing insurmountable though!
- Jens - Is the hot water in the Siano building produced by solar powered electric heat pumps or by solar collectors where the water is heated on the roof?
- Solar electric power is powering heat pumps → System is purposely oversized
- Jens, On Siano, you don’t mention putting refrigerators and freezers on the loop. This can be done especially for commercial kitchens, but ultimately any refrig or freezer. Not only is the equipment more efficient, it lasts much longer. What do you think?
- Usually heat is rejected to outside even in the winter time and is not recovered for heating
- This would add a huge amount of complexity and we’ve already reached a high efficiency in those apartment buildings
- Jens - did you include waste water heat recovery? If not, will you in the future?
- It’s important to make all the hot water from renewable sources to begin with and then consider how we use waste heat. The heat necessary to heat the hot water in order to keep our loopfield smaller. With the waste water heating → it makes the loop more inefficient. Open to it but need to see effort vs. benefit
- Where was the water on the floor coming from? I thought it might be condensation on pipes
- Zero Place - The contractor was power washing the floors in the basement. The picture was before commissioning, and all the pies are insulated, so they do not condensate.
- Jens, How does multistage hw production impact the pumps. If the temperature rise is lower, then the flow (GPM) is higher. Will this make pumps work harder?
- Probably going with the assumption that theres a single pass through, heat pumps bring up temperature 40 degrees F to 140 degrees F from a single pass through, so if you went to a multi pass through or reduce the temperature rise than the GPM is much higher. With the multi pass through you can run cooler water through the heat pump during the temperature rise. When the load water is colder it puts less stress on the heat pumps which increases the efficiency. If they can operate at a higher load temperature the efficiency is lower and the stress on the equipment increases significantly.
- Can you explain again how the hot water system allows the smaller loop field?
- All multifamily buildings we dealt with in NYS, even in upstate New York, are cooling dominated, due to their high energy density. Meaning that annually more energy is rejected into the loop field for cooling than heat is extracted during heating conditions. Thus the loop field size needs to be designed for the cooling load. If heat is taken out of the loop field all year around by the hot water generation, it balances the annual loads on the loop field much better, thus the loop field capacity can be reduced.
- Jens, Did you build your indoor mechanical room piping on site?
- Obviously it was assembled onsite, but it was custom designed and built with the help of Phoenix Energy supply and Earth sensitive solutions (John Manning and Jarred Fortna). It was pre-built by Steve Couse (Earth Energy Connections) in his shop.
- I like the use of thermal storage mentioned at the beginning. Tony’s project could have used the concept of using cooling towers in winter to subcool the soil below. I think for larger geothermal projects and any geothermal based district system, the free use of subcooling in winter and heat banking in some northern places can be a great way to drive to decarbonize.
- Delivering as much heating to a system through the GSHP enables us to deliver heat to water. Being able to utilize heat is critical to design.