Our Green Building
Making 70 South Street eco-friendly
Built For Efficiency
The guiding principle of our Co-op is health, from quality foods and products to a flourishing community to a healthy planet. All through the dreaming, planning, and construction of 70 South Street, making our store as efficient and green as possible was always a top priority. The building is constructed to be airtight and thoroughly insulated, with high-efficiency windows. We also emphasized using low or no-VOC materials.
Natural Light
Many conventional grocery stores are constructed without much natural light. Windows are a rare feature, making the interior a glaring, fluorescent environment, removed from all sense of time and place. Our southeast-facing window bank in the produce department lets in a vast amount of natural light, which reaches all the way to the meat case across the store. The Café seating area has windows all around. Not only does this create a more natural feeling environment for our shoppers and employees, but it reduces the need for interior lighting. We also use full-spectrum light bulbs in the store lighting.
trees & Native plants
In order to construct our building, we had to cut down some trees. Once we were moved in, we undertook the replanting of the surrounding area and in beds around the store. The total number of trees planted was 473. That’s 11 trees in the outdoor dining area, 30 trees in the parking lot islands, and 432 trees around the perimeter slope. The mix of trees includes paper birch, white pine, black spruce, white spruce, red maple, river birch, pitch pine, apple serviceberry, and yellow birch. A generous donation from a Co-op owner fully funded this project. The landscaping also included planting many native plants.
Air Circulation
Did you know that the Co-op’s environmental system is designed to change the air in the retail area 6-10 times per hour? The ‘make-up’ air is brought in from outside and conditioned (warmed or cooled) before being sent to the heat pumps in the area. The heat pumps add this make-up air to the air they are circulating in the area. The return air (the air being pulled out of the store) is pulled back through a separate system of return air ducts and exhausted to the exterior on the back of the building. On its way out it goes through the same unit that supplies fresh air to the store and the old air transfers about 70% or so of its heat to the incoming fresh air before that air is heated (during cooling season the outgoing air picks up the heat of the incoming air).
Part of our Solar Array, photo courtesy of ReVision Energy
Our Solar Array
Right from the start, we knew that we wanted our new Co-op to utilize the sun’s energy. That’s why our roof is so massive. Now it’s home to over four hundred panels, which went online on December 16, 2019. The 414 panels can produce 350 kWh on a sunny winter day (offsetting around 40% of our energy costs). In the summer it will produce even more.
If you’re scratching your head, wondering what exactly 350kWh means, that’s Kilowatt-hours or 1,000 watt-hours. You can check out a live feed of our solar productions here. If you aren’t familiar with terms like kWh, MWh, and GW-hours, you can use this link and brush up on your electrician jargon.
Our 414 Solar Panels Generate Enough Power to:
Brew 7,828,640 Cups of Coffee in a year
Bake 183,483 Chocolate Chip Cookies in a year
Light a home with LED lightbulbs for 244 Years
Cook 440,361 Bowls of chili in a year
Offset driving the perimeter of the United States 36 times
Keep 143,998 pounds of carbon out of the atmosphere every year
See Pictures of the solar installation here.
Waste-Heat Retrieval
Grocery stores need lots of refrigeration, from the coolers and freezers on the retail floor to the walk-in units for back stock. Refrigeration is a big reason why traditional grocery stores have such large carbon footprints. Not only are they energy guzzlers, but they also tend to be quite wasteful, pumping hot air out into the atmosphere without unitizing that power source. We wanted to counteract that as much as possible, so we invested in a waste heat recovery system. This fancy piece of machinery captures the heat produced by our cooling systems and recycles it to heat our new building in the winter and cool it in the summer. It also heats all our water. The system is composed of a variety of elements: the heat pumps, the cooling tower, the refrigeration equipment, the controls, and the heat recovery equipment. In general the way it works is that electricity is used to remove heat from the refrigerator and freezer cases and it’s put into a circulating water loop that the heat pumps then use to take the heat out of the loop and put it into the store. The cooling tower is also connected to this loop to eject any heat we cannot use for space heating or hot water. The refrigerators themselves are the most energy-efficient on the market.
Storm Water Drainage
Erosion can be devastating to the environment, and it is often caused by pavement. We needed to have a large parking lot, but we also wanted to be responsible. And so, the Co-op invested in a massive stormwater drainage system. This sophisticated piece of engineering captures the falling water, sends it through a series of chambers, and releases it in a controlled way that will have as little impact on the hill and forest behind us as rainfall would.
EV Charging Stations
The long-anticipated EV charging stations have been installed in the parking lot! You can now plug into either dual pedestal chargers while you shop or eat in the cafe.
The charging pedestals (ChargePoint) were installed by ReVision Energy, who you may remember are responsible for our beautiful solar array. They were paid for in part by a USDA REAP Grant and by MDI’s A Climate to Thrive.
To offset some of the electrical costs, the Co-op is charging $0.25 per kilowatt-hour. That’s roughly equivalent to $1.80 per gallon of gasoline.
Since installation in mid-August, the chargers have offset 144kg of greenhouse gas emissions, that’s like planting 4 trees and letting them grow for 10 years..
We’re excited to provide these chargers to the community and hope that having a charging option in town will encourage more people to switch to EVs or plug-in hybrids in the future.
By the way, did you know that according to market research, by 2025, EVs should be about 9 percent of the U.S. market? How’s that for positive change?
