With energy provided by solar, wood and geothermal, Village Bakery and the Della Zona Pizzeria may be the "greenest" place in Athens. A geothermal system is the latest step toward environmental progress at the two adjacent buildings.
"Our story of reducing our energy needs and striving to eliminate fossil-fuel sources is especially interesting for the long-term benefits," said bakery and pizza restaurant owner Christine Hughes. "The price of fossil-fuel energy is cheap today but will rise as resources are depleted."
The geothermal system was installed recently to handle heating and cooling needs. Village Bakery hired Airclaws Heating & Cooling of Amesville for the project.
Probably because of the Village Bakery lot size, Airclaws chose to excavate a deep vertical loop system, as opposed to one that runs horizontally several feet underground. Vertical loop systems require a lot less surface area.
Five tubes were buried under the parking lot behind the East State Street bakery, extending down about 300 feet. The tubes are filled with a liquid that is pumped through the closed-loop system. In most cases, the liquid is a water/antifreeze solution. That solution is the medium of heat exchange that transports heat energy between the ground outside and the heat pump unit inside.
So why is a geothermal or ground-source heat pump so energy efficient?
"Much of the efficiency is from the difference between air-source heat and ground-source heat," Hughes explained.
In a standard air-source heat pump, the type that's most common for residential use, refrigerant running through coils extracts heat energy from the outside air and brings it inside, where it's released into the indoor environment for efficient indoor heating. Contrary to popular belief, no air is exchanged between inside and outside. A blower fan then distributes the heated inside air through ductwork.
For cooling, an air-source heat pump extracts heat energy from inside, and releases it outside, again using refrigerant and coils. The removal of heat energy inside results in cool air.
With a geothermal heat pump, the ground outside replaces air as the source or repository of/for heat energy. The water-antifreeze solution pulls heat from the ground - which stays at a moderate temperature, around 55 degrees, year round - and brings it inside for heating, using a heat pump to extract and release the heat from the water/anti-freeze solution. In the summer, the heat pump removes heat energy from inside, and pumps it outside via the water solution, where it's "rejected" into the ground, which acts as a heat sink.
The energy savings come from the amount of electricity required to make this happen. It takes significantly less energy to extract heat from the 55-degree underground than, say, from 25-degree outside air. Similarly, it requires less energy to "reject" heat energy back into the moderate temperature ground than into 90-degree air for summertime cooling.
These systems also can provide cheap water heating in the summer, using excess heat from the heat-exchange process.
It's uncertain whether all of these details apply exactly to the Village Bakery's new system, since no geothermal system is exactly alike, though that's the basic science involved.
The cost of the geothermal system was nearly $37,000, according to Hughes, with a little over $9,000 of that coming from a grant from the Rural Energy for America Program. Athens-based ACEnet helped with the grant application.
The outlay also will be softened with a federal energy tax credit which Village Bakery will be applying for this year, according to Bob O’Neil, Hughes’ partner. “We also received the federal renewable energy tax credit for our solar PV systems last year," he said.
O’Neil called the credits a “great help” that encourage “businesses as well as individuals to invest in renewable energy.” And he termed it unfortunate that “it looks like Congress has not or will not renew this benefit beyond 2016.” The credit is 10 percent for qualified commercial installations of geothermal and 30 percent for residential.
Over the years, Village Bakery has made a series of updates to reduce its energy usage. The total investment has been approximately $110,000, according to Hughes' partner, Bob O'Neil.
"As a civilization, we have a very short window of time in which to make incredibly huge strides away from fossil fuels - and the longer we delay, the more expensive it will be to prevent catastrophic climate change," said Hughes. "The great thing about electricity from the sun and wind, and heat and cooling from the earth, is that the fuel cost will not fluctuate - it's permanently fixed - at zero."
Strictly speaking, this isn't true with geothermal heat pumps that aren't tied to a solar or wind system to provide electricity. Without solar or wind energy, they still require electricity from a regional power grid to run the heat pump and air handler. They just need a lot less electricity than a common air-source heat pump.
All the larger energy-efficiency projects at Village Bakery have involved contractors from the Athens area. Third Sun Solar put in solar panels and Fox Natural Builders installed a wood-fired oven and completed sustainable building work.
"It's very satisfying to spend the business's energy budget locally on energy conservation and generation, and we're looking forward to more opportunities to develop the local clean energy economy with more partners," said Hughes. "Ideally, the energy needs we can't meet on site will come from a locally produced solar farm or solar garden."
Hughes added, "We have more work to do to reduce our energy needs further - more insulation, better windows, and more. We can borrow money and invest today to save money over our lifetime."
She wants to add wind energy and is thinking about contracting with Arcadia Power for that but is waiting to find out more about Athens County's energy aggregation plan. "We will decide to join the Athens plan if it fits better into our long term vision for a clean local economy," she said.
Village Bakery recently opened its doors to the public to showcase its geothermal and other renewable energy systems. A tour was sponsored by the Appalachian Ohio Sierra Club and the club's Sustainable Living Network project.
"We started (SLN) in 2011 as a way of highlighting local examples of people who have lowered their carbon footprints and improved the sustainability of their lives," said organizer Ed Perkins. "There is a lot of expertise in this area, and the SLN gives folks a chance to learn from those who are doing it."
An estimated 20-25 people attended to see the first geothermal system installed at an Athens business. Hughes said she hopes they liked what they saw and will consider it a source of energy that they can use, too.
"We want everyone to have the opportunity to be free of fossil fuels for their energy needs," she said. "Our goal for clean-energy security is meaningless if it's just for ourselves. That's why we try to share what we're doing with our customers and with other businesses who are ready to take more responsibility for our energy consumption." - Athens NEWS Editor Terry Smith contributed to this article.