What’s to do with all of this dazzling, but overwhelming sunlight?” was the question we first asked ourselves upon the return to the family home. We had been away from Texas for seven years to the cooler climes of the West Coast and abroad. In that time the planet had grown incrementally hotter. The 110 degree summer threw a shocking homecoming. The aquifer was low, electricity for AC prohibitively expensive, and an uninsulated house whose brick walls wouldn’t cool down once they warmed up under the southern sun all made us look for an answer.
It was then we started looking into solar panels. Running the AC just didn’t make sense in the long run. We know that when coal is burned, which releases CO2, it creates a hotter climate by not allowing heat to escape. We knew that ultimately the best way to cool our house, not just now, but also in the future, was to burn less electricity, burn less coal.
There were the calculations to consider. How much electricity do we normally consume? How much southern facing roof space do we have where the sun shines hottest and longest? Are batteries to store extra electricity necessary? Is grid-tie a better option where we can sell any excess electricity back to the utility?
We don’t consume much electricity, we found out. We have no TV. We leave lights off in empty rooms. We open windows to cool and dress in sweaters to warm. One vendor who looked at our heating and cooling bills surmised that CPS hates to send us a bill because they lose money doing so. We also discovered that we had little southern exposure unless we were to cut down the 100 plus year old cypress and pecan trees in our yard. We reasoned, however, that if we cut those trees to increase the sunlight on the house we would also be increasing the heat absorbed by the walls and roof. Not to mention that reducing trees means reducing nature’s ability to absorb some carbon from the atmosphere. So we calculated that we had just enough roof space to cover our consummation of 3800 watts, and then some. Since CPS only pays back 1/10 of what they charge us for electricity, we determined that we only need enough solar panels to break even and wouldn't benefit from expensive batteries.
We had decided to invest in solar panels for our hot tin roof—although with the rebate that CPS gives and the federal tax deduction, our "investment" was substantially reduced. The question was, what solar company to engage?
We attended a Solar Tour San Antonio event and visited a number of residential solar installations in town, collecting business cards as we went. We followed up with the companies represented there. Most of the salesmen we talked to rejected our desire to install solar because we didn't fit the profile of their clients—in other words, we didn't fit their rubric of profitable. We didn't have a true south-facing roof (our back roof faces southeast and southwest), plus our roof is very high and steep—read that “a pain to install.” In addition, the roof is partially shaded by century-old pecan and cypress trees. On top of that, our energy consumption is low, meaning that we didn’t need many panels to cover our needs, anyway.
Undaunted, we kept calling solar companies, making online inquiries, and wading though sales spiels. Finally, we struck gold when we called Solar Tech Technologies. Owner Mauricio McNish-Jay came in person to our door in answer to our call: a slim, gentle, Caribbean man wearing a broad-brimmed hat.
Mauricio was not put off by our low consumption—no TV, no AC, line-dried clothes, solar oven—and in fact made suggestions of other ways we could conserve energy. And instead of being scared away by our towering roof, situated to minimize solar gain, he rose to the challenge. He is, after all, an engineer first and a solar installer second.
Mauricio asked to borrow our ladder, the 40-foot tall spindly tower that we reluctantly use to clean the gutters. He ascended fearlessly—unfazed by the height, the gentle but daunting breeze, and the brilliant sun instantly heating the aluminum rungs while casting a large round shadow from his silhouetted hat. He was familiar with the position of the house from a Bing mapping study (see link below!). Studying the standing seam height and roof slope and calculating annual shade patterns, he figured that we could fit the requisite number of panels on our southeast and southwest roof surfaces to cover our consumption and then some.
To compensate for the shade trees that we refuse to trim, he suggested that we use mini-inverters, one for each panel, so that a bit of shade on the panel would not compromise the whole system, but only knock out the panel currently in shade. Efficient, targeted, and sustainable: that is the beauty of our system. The panels are rated to last 35–40 years. In addition, they shade the roof, keeping it a little cooler inside. We now look at the overzealous sun with admiration. We also get to look at all the energy we’re harnessing from this point on, for free.
To see your house as the sun sees it, check out Bing maps which allow you to see your home from from the north, east, west, and if you’re considering solar, the hot, sunny south. You can try it here: http://www.bing.com/maps. Type in your address. Use the bird’s-eye view and zoom in until you can see the detail. Then, click on the arrows next to the compass and watch as your home is viewed from every possible direction, including—and most important for solar study—the south.
- Patrick McMillan