I live in Vermont, zone 6, where we have 7,771 heating degree days (base 65 degrees). We burn gas in our household for hydronic baseboards; we don’t have air conditioning.
Out of curiosity, I started ball-parking costs for a rooftop solar photovoltaic system, which I would link to a new ground-source geothermal heat pump. I was curious what it would take to get off petroleum and leave the grid, where we get most of our electric power from Canadian hydro sources.
First, the ground-source geothermal heat pump system would run around $30,000. Then, to put up enough rooftop solar to power the heat pump’s compressors, it was potentially another $20,000. We are in a cloudy area and I’d need batteries. Even with the rooftop solar, I would still have to tap into the grid to kick over the 40-amp geothermal compressors. That’s a total of $50,000.
At 5 percent bank rates over 30 years, that’s $270 a month ($3,240 a year), minus the deductibility and the state and federal tax credits. It’s more than I pay for my gas bill now. But my gas payments are in cash, and I don’t have to sop up so much credit nor assume debt to pay the gas company.
Worth it? Not really. In fact, that sort of a solar-geo setup is a trophy system. It’s an impractical fantasy — and bad energy policy — to think it could be viably installed on a house-by-house basis.
I costed-out these energy solutions because of some information I learned from Robert Bryce’s book “Power Hungry: The Myths of ‘Green’ Energy and the Real Fuels of the Future.” As glamorous as it is to express love for solar and look with pride at windmills spinning on ridgelines — believe me, I’m a museum-quality environmentalist — you have to ask if those systems can deliver a meaningful contribution to our grid or energy reserves. In addition, that has to be seen in the light of how much energy it takes to manufacture the alternative generators and how much land is required to make them work.
Robert Bryce points out that California’s peak electricity demand is about 52,000 megawatts, of which around 17,000 megawatts will soon have to come from renewable sources by law. The new California-based $2 billion Ivanpah solar plant will provide a whopping 370 of those megawatts. The size of that solar farm is 5.5 sq. miles. That’s $2 billion to produce .02 percent of the total required renewables.
How about wind?
Bryce further points out in a recent New York Times op-ed that the Texas-based Roscoe wind farm covers about 154 sq. miles and generates 781.5 megawatts. In California, that would add another .04 percent of power contribution toward the 17,000 megawatt required renewable total.
The answer is deducing overall energy demand through new codes and efficiently burning domestic gas. Reducing demand will not come from uncoordinated volunteer efforts. It will come from government regulation.
Articles I have written in the past that support government energy regulations have been met with negative responses from some readers, so keep those cards and letters coming. But honestly, stricter government regulation of the energy performance of a structure is what’s required to solve our energy consumption problems, which are real and will only get more costly.
The 2012 implementation of the (proposed) International Code Council International Energy Conservation Code is a good start, and its goal is a 30 percent incremental energy savings compared to the 2006 IECC. The IECC approach is ideal because it focuses on thermal envelope performance, which is the keystone to any energy-efficient future. As a companion to the IECC regulations, we have seen a dramatic rise in innovative green energy products and efficient HVAC units.
I’m all for solar and wind solutions — the more innovation, the better. For instance, hyper-low-friction, rooftop, mag-lev wind holds promise. But solar and wind have to be seen in the unglamorous light of their embodied energy and how much they can realistically and cost-effectively contribute to our energy future.
John D. Wagner is an award-winning author of many books and articles about construction, and a frequent contributor to the industry’s leading trade magazines. A sought-after speaker for industry events, he can be contacted at JohnDWagner.com. Read past columns at rdbmagazine.com.