Crawford House goes green at the speed of light
No, Crawford House is not getting 900 satellite channels or attempting to communicate with space aliens.
The large structure recently erected just outside the building is a photovoltaic solar array which is currently generating electricity to decrease Crawford House’s consumption of nonrenewable resources.
In keeping with the company’s covenant to be environmentally friendly, the 12-panel array is expected to provide approximately one-third of the house’s overall electricity usage.
The panel, which cost about $20,000, was made possible by a grant to the environmental studies program from the Appalachian Regional Commission (ARC).
Though Crawford House is seeking the internationally renowned Leadership in Energy and Environmental Design (LEED) certification, this move was actually not required in order to receive approval. According to Bruce Guillaume, the program director of Crawford’s resident company Mountain Challenge, LEED is primarily concerned with efficiency.
“This is about generating some power using a renewable source,” Guillaume said.
Guillaume explained that, while they have already cut Crawford House’s electricity usage by 40 percent over the past year seeking LEED certification, being able to supplement the energy they do use with a renewable resource is a step toward conservation.
“It’s real easy to forget that you need to conserve and be efficient,” Guillaume said.
The solar panels work by capturing the sun’s energy and generating a direct current of electricity. In this form, electricity is not usable, so each individual panel of the system has its own micro-converter that turns the electricity into alternating current. This is the energy the house utilizes.
Attached to the panel is a computer that is connected to the college’s network. This computer records the amount of kilowatts (kWh) the solar panel is producing at all times and allows users to view this information.
Though Crawford House is technically a commercial building, it operates much the same as a residential home due to its size, construction and consumption. While the ARC grant required that some kind of solar project be conducted, it did not distinguish between residential or commercial, so the environmental studies program saw this as an opportunity to raise community awareness.
“We purposely wanted to get something that was residential scale,” said Dr. Mark O’Gorman, who is the coordinator of MC’s environmental studies program and the ARC grant administrator. “The environmental studies program received a grant from the ARC, and this ARC grant is trying to leverage monies from local renewable companies to have people like us … build things like this on campus. We can bring people from the community to these places and say, ‘Here’s how it works. Here’s what it’s like. Here’s what’s going on.’”
O’Gorman believes that, with the help of Guillaume, the ability to educate the public about Crawford House’s solar array will encourage residents to consider incorporating solar power into their own lives.
Though the array’s price might deter locals, the amount of money saved in electric bills will be tracked and recorded over time in order to determine in how many years the unit will essentially “pay for itself.” O’Gorman guessed this would be between 15 to 20 years, though admits that it is way too early in the project to make any kind of an estimation.
Also, some residential users may qualify for government grant money to install their own solar arrays.
One way the solar array’s performance may be improved is by altering the angle at which the unit is facing. Efficient Energy of Tennessee (EETN), the company hired to install the solar array, calculated the ideal installation location for the unit and direction for the panels to face in order to receive optimum sunlight exposure.
As the seasons change, however, so does the angle at which the sun will hit the panels. In order to keep getting maximum results from the panels, new angles will have to be calculated and physically altered.
O’Gorman hopes that future environmental studies students will be able to take part in this process, should it occur.
Though the array does not have a battery, neither O’Gorman nor Guillaume are concerned about losing excess energy the panels may generate. Because the panels will probably account for only 30 percent of the electricity required to run the house, the odds of any of it not getting used are slim.
Even in the summer months, when the sun shines longer and stronger, the house will likely be running its air conditioning at a more consumptive rate as well, thereby matching the excess output with excess use.
This relates to the concept of load shaving, which O’Gorman explained.
“The idea is that if you keep track of your building, your building uses energy at different rates at different hours of the day … By 3 p.m. it’s at its full capacity; everyone’s got everything turned on. The concept of load shaving is that we know that whole process is literally a 24-hour bell curve that peaks around 3:30 [p.m.]. If we can find a way to use some other energy source to try to provide energy through other than conventional means … what we’ve done is we’ve used a renewable energy source to reduce the overall energy that a building has to get from conventional sources.”
One option for the implementation of this solar project was simply to sell the generated electricity to the Tennessee Valley Authority, but Guillaume “thought it would be cool” to put it into a building and actually measure its usage.
Eventually, there will be a real-time display in Crawford House to show how many kWh are being produced at any given time.
This solar array is doing more than helping to power a 150-year-old farmhouse. Local Maryville city government is looking to this project as an example of future options concerning renewable energy, and the college’s participation in this project may lead to future campus environmental innovations.