The sun shines a lot in New Mexico, and homeowners are taking advantage of it. The amount of power generated by residential photovoltaic systems in New Mexico has risen by 2050 percent in the past five years. And nearly 800 residential systems were installed in Santa Fe County since 2008.
And if you’re wondering about resale value, the news is equally positive. A 2013 analysis by the Appraisal Institute, Chicago, found that photovoltaic systems “typically increase market value and almost always decrease marketing time of single-family homes in the Denver metropolitan area.” And the results of a larger study by the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, released earlier this year, found that the “PV premium” amounts to about $4 per watt — in other words, a 4-kilowatt system adds about $16,000 to the value of a home.
Photovoltaic modules, which use light (photons) to move electrons in a circuit — what’s known as the photovoltaic effect — are much more efficient than a decade ago.
One of the advantages of producing your own power is “net metering.” When you have a standard grid-tied system, the power from your solar array that you don’t use goes into the utility grid and you accumulate credits that you can use at night and in the wintertime.
“I have actually paid nothing to PNM since I installed my system,” said Joyce Lathrop, who had Positive Energy Solar install a 2.29-kilowatt system at her house in July 2014. “There were actually two months in the winter where I paid a bill, but it nets out to zero.”
Another reason to go with PV is that it offers some degree of self-reliance. “There’s a lot of uncertainty about where our energy will come from, and about regulatory issues, and storms that can cause power interruptions, so people are thinking more about independence,” said Karen Paramanandam with Positive Energy Solar in Santa Fe.
If you decide you want to go solar, gather 12 months of your electric bills and call a solar installer for a free evaluation. You want to know what size system you need and where to put it — “what will get you maximum power with the available shade-free square footage,” as Paramanandam put it.
Installing on the rooftop requires that the roof be sound and solid. “Can it take the weight and the wind load? It’s a complex design challenge,” she said, adding that this isn't an issue with ground mounts; plus, those are preferable because there will be better ventilation. PV panels lose efficiency when they overheat.
Some people choose to add a mechanism that turns the array to follow the sun. That can increase your power generation by up to 40 percent, but trackers require regular maintenance. A static array can basically sit there generating power untended for decades.
What about camouflaging PV? Siting solar arrays is an ongoing challenge in Santa Fe’s historic district and in Eldorado, to give two examples. “We work with the city’s Historic Districts Review Board and homeowner associations and architectural review boards and at the request of clients typically we’ll put out a letter to neighbors,” Paramanandam said. “We try to be an advocate for best practices in solar.”
The typical Santa Fe house requires a 4-kilowatt system, or about 12 SunPower-brand modules. On a good day they will produce 700 kilowatt-hours. If your home electrical system is up to snuff and there are no issues with your roof or other special circumstances, such a system will cost you about $23,000.
The solar-generated current flows into an “inverter” box that changes the DC current to AC, and then proceeds to your main electrical panel. “It has its own breaker and there’s also a safety disconnect so you can isolate your system from the grid. Your solar power feeds your load first, then the excess gets pushed out onto the grid; that goes through a net meter, which the utility installs,” Paramanandam said.
“The other leap in technology is in batteries. Tesla Motors and [company CEO] Elon Musk have pushed the boundaries in storage, so we’ve been getting more and more requests for battery-integrated systems. If you have battery storage, we install a critical-loads panel. Let’s say you have someone on insulin and you can’t have the fridge go off; that will be backed up to the batteries.”
A battery system is about 50 percent more, so a new system with battery storage is closer to $40,000.
Whether or not you incorporate battery storage, you can get some relief on the system cost through income-tax credits. There is no limit on the federal income-tax credit: a dollar-for-dollar reduction of 30 percent of the cost of your photovoltaic system. The 10 percent New Mexico income-tax credit has a $9,000 limit.
REC incentive disappears
Besides net metering, PV owners have also enjoyed getting checks from PNM and other utilities based on a “renewable energy certificate.” “With this, you’re giving the utility company that pays you RECs the right to claim your credits and then PNM, not you, is the carbon-neutral entity,” Paramanandam explained. “But we just got a letter last week [mid-July] informing us that the REC program for systems under 10 kilowatts is full. They’re no longer accepting any new REC agreements.
“There is talk of a national renewable energy portfolio standard and if that happens, who knows what the local utility companies will have to do to meet that standard? Best scenario, they re-up the REC program.”
“I get 3 1/2 cents per kilowatt-hour for being a producer,” Lathrop said about the REC checks she has received. “I had photovoltaics installed on a previous Santa Fe house some years ago and I think I was getting 12/1/2 cents and a year ago it was down to 3.5 cents and now it’s gone? That’s ridiculous.
“However, most people I know who have done this don’t do it because they’re doing to get paid by the utility company; they do it because they have the money and it’s the right thing to do, plus the tax credits on your income tax makes a huge difference.”
Lathrop said she figures she will recoup the total cost of her PV system in nine years, through electricity savings. Her 10-year REC contract will also expire at about that time. “But I will still come out ahead because I’ll probably make more power than I need. I would say there should always be an incentive to do this until it becomes cheap enough that people can do it without any incentive.
“I think real change is going to be a long time coming,” said Lathrop, who also complained about the paucity of electric-car charging stations in Santa Fe. “Because for whatever reason those people who have bought into gas and oil can’t quite see that that’s not the future.”
New Mexico Energy, Minerals and Natural Resources Department's solar site: www.emnrd.state.nm.us/ECMD/RenewableEnergy/solar.html
New Mexico Solar Energy Association: www.nmsolar.org
Specialists in solar hot water and heating include Amenergy (amenergynm.com/solar-thermal), SolarLogic (solarlogicllc.com), and Solar Wise (solarwiseusa.com).