Oak Park residents Mac and Harriette Robinet installed ground source heat pumps (geothermal system) outside their home in 2011 and 12 solar panels on their garage roof last summer. Mac, who worked as a physicist at Argonne National Laboratory for 39 years, estimates they are already saving 20% on the cost of energy.

The geothermal system reduces their consumption of gas to virtually zero, he said. The ground source heat pumps use more electricity than a gas furnace, and because electricity costs about three times as much as gas, the difference in their energy bills hasn’t been that significant compared to years past. But before they had the geothermal system installed, they did not have central air conditioning. With that added benefit taken into account, the savings are much greater. 

Robinet’s system is rated at five tons. “A ton,” Mac explained, “is a measure of cooling equal to the cooling a ton of melting ice would produce in a 24-hour period.”

In addition to saving on gas, their solar panels provide some of the electricity they would be paying ComEd for. 

“Our system will produce 3500 kilowatt hours of energy,” he explained. “Right now the cost of electricity is about 10 cents/kilowatt hour, which means we will make about $340 a year.” 

On summer days when the sun shines for 10 hours, he added, “The solar panels will actually generate more electricity than we will consume and that surplus will be put back on the grid and credited to our account.” 

The market cost of the 12 solar panels installed on his garage was about $12,000, but with a 30% rebate from the federal government and a 25% rebate from the state, the Robinets paid only $5,000 to add solar to their home. 

That means the solar panels will pay for themselves in about 16 years. For those who protest that is too long to wait, Mac responds that if you look at what you pay to be green as an investment, you are making about 6% a year. “You can’t get anywhere near that at a bank,” he noted.

However, the primary reason Mac and Harriette installed the earth-friendly energy sources was not financial but ethical. 

“We are octogenarians,” Harriette explained. “We won’t be around for the payback. We did it primarily for the community because of global warming and moral conviction.”

Mac said that for every kilowatt hour ComEd produces they dump into the air a pound of carbon dioxide, and with their solar panels generating 3500 kilowatt hours of electricity annually, they will be reducing the amount of CO2 in the air each year by almost two tons. 

The geothermal and solar systems combined will reduce their carbon footprint by 70%, eliminating eight tons of CO2 from the atmosphere.

Harriette said that being a scientist didn’t give Mac a head start in becoming aware of the problem of global warming. “You learn; you grow; you read; you become aware,” she said. “I don’t think we knew it any sooner than anyone else.” She paused and added, “But then again we are with a group of people [in this community] who are like that.”

Mac smiled as he told the story of how he became aware of ground source heat pumps years ago, right after he had installed a brand new, high efficiency gas furnace. Frustrated at having invested money in an expensive furnace which he would rather replace with geothermal, he consoled himself that the warranty for the appliance was 15 years, not too long to wait for what he really wanted. As it turned out, he had to wait 30 years. The new furnace proved to be not only efficient but long-lasting.

In the meantime, he read everything he could about geothermal. He went to Triton and took every course on refrigeration and air conditioning. He joined the International Ground Source Heat Pump Association to learn even more.

Then he began advocating for geothermal. 

“It made so much sense to me,” he recalled. “Every time I heard that someone was replacing a furnace, I’d write them a letter telling them about ground source heat pump heating and cooling, but nobody ever responded. I thought maybe I was doing something wrong.”

It was while Mac was a member of the Oak Park Energy Advisory Commission that his persistence paid off. He proposed that in order to get a permit for a large building, the developer should have to include geothermal in the construction. He argued that not requiring ground source heat pumps was, in effect, a permit to pollute. When the lawyer replied that they could not do that sort of thing, the commissioners came up with a creative response.

The ordinance they wrote requires an energy analysis comparing the cost of heating and cooling using a geothermal system with the cost of a conventional system and predicting the operating and maintenance cost, energy consumption, and production of atmospheric carbon dioxide. 

“The thinking,” Mac recalled, “was that anybody who would do the analysis honestly would have to come to the conclusion that they would have to use a ground source heat pump. Why would you not?”

The new Walgreens at the corner of Grove Avenue and Madison Street was the first business to install ground source heat pumps because of the new ordinance, and the second was the Grove Apartments across the street in the old Comcast Building. 

“I was really pleased with that,” said Mac, “and as far as I know we’re the only village in the country with that kind of ordinance.”

Mac’s persistence in advocating for a greener world is an example of how the Robinets operate. They tend to be quiet people who would rather walk the walk than talk the talk, and they have a long history of acting on what they believe. Being green for them is a lot easier than being black when they were growing up in the 1930s and then when they moved to Oak Park in 1965. 

Harriette, who was born and raised in Washington D.C., remembers how her parents reacted to a lynching in nearby Arlington, Va. “They had taken a photograph of it,” she recalled, “and they were discussing it in our living room. There were fires and the body hanging and white people around it. As soon as my mother saw that I was in the room and seeing the picture, she screamed at me, ‘Get out of here, get out of here and don’t come back!’ so I ran away from the room where adults were whispering.”

Mac, who grew up in a little town in Louisiana, said that every time his family left the house, his parents would tell him and his brother, “Don’t cause trouble.” At the time, he didn’t understand their fear because “they did a lot to shield us.” Later, as an adult, he came to understand how vulnerable they were. “I became aware that they were afraid,” he said. “We had a car, but at any point they could say, ‘We’re going to call that loan on your car.’ My dad worked in the sugar mill constantly. He was afraid to say no when they called him in to work overtime.”

When the Robinets moved to their present home on Elmwood in 1965, few black folk lived in town and for some residents, that was the way they wanted to keep it. Although many of their neighbors welcomed the couple, Mac and Harriette received some hate mail. Harriette remembers helping organize marches for open housing in her living room with the Citizens Committee for Human Rights.

“We believed in caring for people,” said Harriette.

According to the village of Oak Park going back to 2001, 10 homes in Oak Park have installed solar to date. That number is sure to rise.

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Tom Holmes

Tom's been writing about religion – broadly defined – for years in the Journal. Tom's experience as a retired minister and his curiosity about matters of faith will make for an always insightful exploration...

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