Replacing the Sanctuary windows
Purchase of the rooftop solar panels
Geothermal Heating Ventilation and Air Conditioning (HVAC)
Frequently Asked Questions:
(click on each question below to view or hide the answers)
What are the sustainability measures recommended jointly by the Energy Committee and the Board of Properties?
- Replace the windows in the Sanctuary with insulated, energy efficient windows. This will help complete “sealing the envelope” of the church building.
- Purchase the roof top solar panels. The panels are currently leased. The owner has realized most of the tax benefits of the array so we can now purchase the array at fair market value, about $150,000. This will save approximately $11,000 per year we have been paying for the electricity. It appears we will also be eligible for “Solar Renewable Energy Credits” (SREC) payments that will be approximately $20,000.
- Replace the HVAC system that uses oil burning boilers with a ground source geothermal HVAC system. This includes replacing all seven rooftop units which will also then provide air conditioning to all areas of the church.
Why would we want to replace our HVAC system and make further investments in sustainability of our church building now?
- In 2014 the congregation charged charge the Energy Committee to guide us to be better stewards of God’s creation through increased energy efficiency and renewable energy with the goal of achieving net zero energy usage. The recommendations in this sustainability discussion are the result of 8 years of work toward that goal.
- The HVAC system’s major components – the two oil burning boilers and the seven Roof Top Units (RTU’s) that provided hot air heating to all zones and air conditioning to some zones – are at the end of their expected service life. We face steadily increasing maintenance costs and increased probability of failure as time goes forward.
- The Inflation Reduction Act of 2022 restored a tax credit for 30% of the total project costs for geothermal HVAC systems. An additional 10% credit is available if domestic products and union labor are used., The act provides for a direct payment of these credits to non-profits that otherwise would not be able to utilize a tax credit.
Have we considered other options besides geothermal for replacing the HVAC?
- Geothermal is the only technology that will achieve our goal of not using fossil fuels and moving toward net zero energy consumption.
- Modernizing the fuel oil boilers for heating and high efficiency natural gas boilers were evaluated. Modern oil burning boilers are significantly less energy efficient than natural gas (88% compared to 98%) and of course both of these technologies burn fossil fuel.
- Geothermal HVAC provides both air conditioning and heating.
-Oil and natural gas boilers provide only heating. Air conditioning is now provided by the roof top units (RTU’s) powered by electricity.
-Our present RTU’s do not provide air conditioning to the classrooms, the sanctuary, and Village Hall.
-The geothermal HVAC system will provide air conditioning to all areas of the church. Additionally, air conditioning provided by geothermal system is more efficient because the system is cooled by the earth (55 degrees) instead of by outside air (70 to 100 degrees).
How does the environmental impact of the options compare?
The geothermal system will not burn fossil fuel so there are no direct carbon dioxide and other emissions. If we assume all the electricity used by the geothermal system is from the power grid, the geothermal system will produce 75% less carbon dioxide emissions than gas or oil heating.
How much would the installation of a geothermal system and a natural gas system cost?
- The cost of the geothermal HVAC system for our church (based on a detailed engineering design) was estimated by a professional project cost estimating firm in June 2022. The estimate is $2.4 million. This estimate appears to be conservative with several significant reserves allowed for variables.
- The Inflation Reduction Act direct payments would reduce the geothermal cost to $1.7 million and if we can also meet the requirements for US parts and labor, the cost would be further reduced to $1.4 million.
- TE2 Engineering estimated the cost of a natural gas system would be about $1 million.
Both systems require a new integrated control system for the building to replace the 3 control systems we use today. The cost for a new control system is included in the project estimate.
How much will the three sustainability projects cost?
- The replacement of the sanctuary windows with energy efficient windows is estimated to be $150,000. The purchase of the solar panels is estimated to be $150,000. The geothermal HVAC system is estimated to be $2,400,000.
- The total cost for all three sustainability projects is estimated to be $2.7 million.
Financial incentives will be a minimum of 30% of the cost of the geothermal systems. This would be a direct payment to the church of $720,000. If the geothermal project qualifies for the additional 10% credit (US components & union labor), there would be an additional direct payment of $240,000. If the new sanctuary windows meet the criteria for energy efficiency, there can be a direct payment of 30% of the project cost. That would be $45,000. Thus the potential direct payment incentives range from $720,000 minimum to $1,005,000.
Are there financial incentives for a new HVAC system?
- The “Inflation Reduction Act” (IRA) provides tax incentives for new geothermal systems: There is a 30% tax credit (30% of the total project cost) in the year that the systems are put into operation plus an additional 10% tax credit if the components are made primarily in the USA and union labor is used. This is a total of 40% of the project cost.
- The IRA has a special provision for all non-profit organizations. It provides for payment of the tax credit as a direct cash payment to all non-profits including churches.
There are no incentives for fossil fuel systems such as natural gas and oil.
What annual maintenance would be expected for a geothermal and a natural gas system?
- The annual maintenance for a geothermal and a natural gas system are similar. The rotating equipment (pumps, fans, belts, etc.) and moving components (e.g. dampers) need to be checked annually. The various filters are checked semi-annually.
- The maintenance of a geothermal system is expected to be somewhat less because no combustion is involved.
- The geothermal in ground components, wells and piping requires no maintenance.
Do we save any annual operating costs with geothermal compared to other options?
- Obviously, we would not need to purchase fuel oil. The church spent about $46,000 on fuel oil in 2022 so those costs would be saved.
- Natural gas costs would be about 32% less than oil costs for our building. If we use 2022’s oil costs of $46,000 as a baseline, natural gas would cost about $31,000 for the same amount of heating.
- At this point, we are making the conservative assumption that the cost of electricity is about the same for both a natural gas and geothermal system.
- The big factors driving operating costs as we look into the future are what we think oil, natural gas, and electricity prices will do.
Is the “ease of operation” any different for geothermal?
Geothermal appears to be the simplest and thus the “easiest” to operate. It also appears that a major factor in ease of operation is the choice and design of the new integrated control system for the building.
Will this geothermal system be able to both heat and cool the entire WVC building in both summer and winter without a supplemental heat or cooling source (e.g., a fuel oil or natural gas boiler)?
- Yes. The geothermal system design provides 100% of the heating and cooling needs for the “design days” (hot and cold) of our area.
- Several measures are planned to verify this. (1) When the first geothermal well is drilled, it will be put into operation with a test rig to verify its heat transfer capacity matches the assumptions of the system design. (2) One of our two current fuel oil boilers will be left in place in a standby condition for one season to provide additional heating if required.
What happens if the system doesn’t achieve its design of providing adequate heating and cooling year-round?
- The geothermal system design concept and equipment are tried and proven so we believe it is very unlikely that this will occur.
- One of our two current fuel oil boilers will be left in place in a standby condition for one season to provide additional heating if required.
Are there any other similar buildings that use geothermal HVAC systems?
There are a surprising number of buildings in our region that use geothermal HVAC. We are compiling a list and will make that available soon.
Do we need to run new heating pipes or air ducts in the building for a geothermal HVAC system?
- No. Our geothermal system design is called a “hybrid systems” because it uses the existing fin tube radiators in the offices and classrooms as well as the cast iron radiators in the Sanctuary as well as “forced hot air” from the RTU’s to heat the building.
- The only ducting changes will be minor to match the existing ducting to the fittings on the new RTU’s
Our current HVAC system provides air conditioning to the offices, Burt Chapel, Village Common, the crib room & the library. The sanctuary, Village Hall, and the classrooms (basement & second floor) are not air conditioned. Will the geothermal system provide air conditioning to all of the spaces (zones) in the building?
Yes. The design of the geothermal HVAC system replaces all of the RTU’s with new RTU’s that all have both heating and air conditioning.
What are the major components of the proposed geothermal HVAC system?
- Well field – 20 vertical wells, 6 inches in diameter, 500 feet deep with a U-shaped pipe in each. The well field will be under the driveway.
- Three “ground sourced” heat pumps on the footprint of one of the existing oil burning boilers.
New circulating pumps, expansion tank, and control valves in the boiler room to supply the fluid heating loop in the building and ground loop to the wells outside.
- Seven new RTU’s replacing the seven RTU’s we have now.
- A new integrated control and monitoring system.
Why can’t we use a heat pump system that uses above ground cooling like a home heat pump rather than a geothermal heat pump system?
Transferring heat to the outside air in the cooling mode or taking heat from the outside air in the heating mode is inefficient due to variations in outside air temperature and the lower efficiency of heat transfer to air versus to the ground. Imagine you have 90 degree outside air on hot day. Air conditioning equipment will need to work much less to cool inside air if it transfers the heat to 55 degree ground loop water than if it transfers the heat to radiators in 90 degree air. Similarly for heating if the outside air is below zero a heat pump may have difficulty transferring any heat from the air but will work fine with the constant ground temperature of 55 degrees.
How long would it take to complete the geothermal HVAC project?
We have received rough, verbal estimates of 4 months. It could be faster – and cost less – if we are willing to “shutdown” the building so heating and cooling does not need to be provided during installation. An ideal time would be summer of 2024.
Do we lose heating or air conditioning during any phase of the project?
The project could be done without shutting down heating or air conditioning to any portion of the building for a significant time.
Can we continue to use the control system we have now?
No. A new monitoring and control system is needed for technical reasons and to provide a much more robust, non-proprietary, easy to use monitoring and control system.
What is the expected life of a geothermal HVAC system?
- The well field is warrantied for 100 years. The wells are drilled, the U-tube inserted, filled with mortar, and capped off underground. There are no moving parts, just pipes in the ground. No service is required.
- The heat pumps, circulating pumps, and RTU’s typically have a useful service life of 25 years as would the equipment for a natural gas system.
Are there any “side benefits” to the geothermal system or other projects that would be logical to do at the same time?
The church can investigate the cost/benefit of several additional projects that could be done at the same time. The driveway will likely need to be replaced after drilling the wells and running the pipes. While it is torn up, we could:
- Investigate replacing the building’s two clay tile sewer pipes that have been causing issues over the years.
- Investigate installing some electric vehicle charging stations.
- Investigate installing a natural gas backup power generator. The cell phone company with antennas in the steeple may have an interest in this too.