Builder Pulls Plug on Power Co. : Subdivision to Generate Electricity Beyond Own Needs
No monthly electric bills in this desert city where, in the summer, temperatures routinely soar to 112 degrees, and the owner of a conventional home steels himself for air conditioning expenses of $300-$350 a month?
That’s the promise being held out to buyers in a quiet, park-bordered, 24-home development now under construction on Phoenix’s northwest side. Not only are they being assured that, once in place, those homes will trigger no electric bills, but that, as owners, they may receive checks from the utility.
For long-time Phoenix home builder John F. Long, Solar 1 is the culmination of a lifetime fascination with energy efficiency. It’s certainly the first time, anywhere in the world, that an otherwise conventional housing development has been designed as a mini-utility, not merely 100% solar efficient--creating its own electricity directly from the sun-- but capable of producing energy beyond its own needs.
At the heart of Long’s Solar 1 project is the energy center for the development: a rectangular 74-by-131-foot enclosure, bounded by an eight-foot wall that screens it from both the houses and adjacent Osborn Road traffic. The center consists of 3,600 photovoltaic panels (132,000 cells, in all) measuring four feet long, 16 inches across, and slanted on seven-foot racks to capture the rays of the burning Phoenix sun.
“We’re gridded into the electric utility, the Salt River Project,” Long explains, “which means that during the day we’ll be selling our excess energy to the SRP at the peak-hour rate, which is 5.7cents per kilowatt hour and then, at night and on inclement days, we’ll draw energy back from them at, normally, the off-hour rate of 3 1/2 cents per kilowatt hour. Ideally, the system has been designed to produce a zero balance over the course of the year.”
Still and all, Long emphasizes, the photovoltaic system designed for him by Chatsworth-based Arco Solar, Inc. (a wholly owned subsidiary of Atlantic-Richfield), would fall far short of being cost-effective without the utilization of passive components in the homes, themselves--the key element being a building technique more than 800 years old.
“The Hohokam Indians, who lived around here before disappearing about AD 1100, “ Long explains, “didn’t try to fight the environment, but learned to live with it, and the heart of it was rammed earth construction--extremely thick walls with the insulation on the outside instead of the inside so that they acted as thermal storage.”
Thus, the six model homes in Solar 1 come equipped with 21-inch rammed earth walls--a wetted-down mixture of sand and dirt held together with cement (about 7%). The mud mix is poured into forms, packed down with pneumatic hammers and the walls are then allowed to dry.
“It’s like living in a basement above ground,” he adds, “but it was important to me that the houses, otherwise, be of conventional design. Most houses that go heavily into passive solar design end up so funny looking that they turn people off.”
And there is nothing “funny looking” about the attractive Solar 1 homes, which range from two to four bedrooms, from 1,600 to 2,200 square feet and are priced from $110,000 to $125,000. The abnormal thickness of the exterior walls is virtually undetectable.
But, in addition to the rammed earth walls (in terms of insulation rated R-27), other passive features include double-paneled windows, a combination evaporative cooler/refrigeration air-conditioning system, low-use appliances, such as water-saver toilets, solar water heaters and R-50 ceiling insulation. A measure of heat resistance, the higher the R rating the more effective the insulation.
“There are also shade screens on all east/west windows,” Long adds, “and we’ve put infra-red aluminum barriers in the attic right under the sheathing which deflect the long rays of the sun, the ones that penetrate conventional insulation.”
But it is still Solar 1’s role as a mini-utility releasing its homeowners from their dependence on the local electric utility that makes it, in the literal sense of the word, unique.
“There have been some Third World villages that have been equipped with photovoltaic generators,” according to Jerry Reznick, Arco Solar’s manager of marketing communications, “but these are situations where they had absolutely nothing before, and their governments picked up the cost to bring them some sort of basic power--enough for electric lights, water pumping and communications. And there have been some commercial applications of course, but, to our knowledge, no one has tried what Long is doing--making an entire housing development energy-self-reliant this way.”
A critical consideration in Long’s decision, Reznick adds, has been the dramatic decline in the cost of manufacturing photovoltaic cells since their first application as power sources for satellites in the space program in the ‘50s. At that time the cost was as high as $2,000 per peak watt--the term used to describe the electrical output of a cell. As commercial applications began increasing demand in the ‘60s the price dropped to about $200 and then to about $15 per peak watt in the ‘70s.
“Now,” Reznick continues, “it’s down to about half that--about $7.50 per peak watt--and how much farther, and when, it will go lower depends almost entirely on demand. It may have leveled off for awhile.”
Essentially, he adds, the photovoltaic module converts light directly into electricity by virtue of the fact that when a photon (a unit of electromagnetic energy) strikes a solar cell (consisting principally of a silicon diode “very similar to a computer chip”) it sets an electron in motion along a circuit and the light is directly converted to energy.
“Early in the ‘70s,” according to Long, who built his first Phoenix home in 1947 and, in the interim, has constructed more than 30,000 others, “we started concentrating on photovoltaic panels with an eye to the heating of water with which to generate steam, and then using the steam to turn a turbine. But it was just too expensive for single-family homes. The answer lay in directly converting sunlight to directcurrent (DC) and then converting it to alternating current (AC), which is not only compatible with both the utility and household appliances, but which is also a lot cleaner than energy produced by the utility.” (“Cleaner,” because, according to Reznick, a direct creation of energy bypasses the utility’s normal water-cooling process and the waste created in this phase of the conversion.)
Under the guarantee given Long by Arco Solar, the 132,000 photovoltaic cells in Solar 1’s Energy Center will generate 350,000 kilowatt hours of electricity a year (the cost of any shortfall will be guaranteed by Arco for 10 years at peak rates) and each of the 24 homes in the development will be individually metered as to output and input and, therefore, entitled to one-twenty-fourth of the energy generated, or 14,583 kilowatt hours a year.
(In the Los Angeles area, according to a spokesman for the Department of Water and Power, the average home with air conditioning and a heated pool is estimated to consume 10,000 kilowatt hours a year. In Phoenix’s torrid summers, however, when air conditioning becomes a 24-hour matter of survival, kilowatt usage soars, Long says, and an annual consumption of 18,000 to 20,000 kilowatt hours isn’t unusual for a conventional home without the passive energy features in his solar homes. With them, however, annual consumption is on a par with comparable homes in Los Angeles).
“The whole idea of Solar 1,” Long adds, “is that, without changing his life style, the home owner should strike a balance--generating more than his own needs during the peak hours and drawing on that surplus during the off-hours--so that he will never have an electric bill to pay.
“Now if, through his own conservation efforts, he should use less than his monthly allocation, then he’ll get a small--maybe $10 or $15 check--back from the Salt River Project. If he’s wasteful, he might end up having to pay a little. We’re not really encouraging anyone to buy one of these homes if he isn’t already concerned about energy, but, again, we’re not talking about changing life styles.”
Admittedly, Long adds, Solar 1’s feasibility without the Internal Revenue Service’s solar tax credit would have been doubtful. And, unless Congress intervenes, these tax credits are slated to run out at the end of this year.
“I’d estimate,” Long continues, “that, without the tax credit, the active and passive energy devices used--and which, incidentally, the home buyer doesn’t pay for, we pick up the entire cost of them--would add about $50,000 to $60,000 to the price of the house. And, even if you amortize that over 30 years--which is the estimated life of the photovoltaic panels--you’d be hard-pressed to justify the cost effectiveness. But, of course, if the price of photovoltaic equipment continues to come down as it has in the past, well, that could put the whole thing in a different light.”
(The Federal solar tax credits, a spokeswoman for the IRS here said, allow a write-off of 40% of the cost of active and passive solar equipment up to a maximum of $10,000--or, in Long’s case, 24x$10,000--plus the other tax and depreciation considerations already in place).
Underlining Long’s contention that the cost of Solar 1’s precedent-setting energy-generation equipment is not being passed along to the home buyer is the fact that all six models being built for the development are also available in other parts of the city at the same listed prices with all of the passive energy features--including the rammed earth construction--but not plugged into Solar 1’s photovoltaic Energy Center.
“My daughter’s been living in one of them for several months,” Long notes, “and we’ve been monitoring it very carefully with wall sensors and other techniques, and we estimate that--even without being gridded into photovoltaic panels--her utility savings are going to be in the 30% to 50% range.”
For the first five years, Long continues, “we’ll retain ownership of, and manage, the energy center, to satisfy IRS requirements. But then it’ll be turned over to the homeowners’ association. Technically, after five years, according to the IRS, the energy center has to be sold to the highest bidder, but since it has no value except to the homeowners’ association--Arco’s 10-year warranty is void if it’s dismantled--its value at that time will be negligible and I’d guess it wouldn’t amount to more than a few hundred dollars per homeowner.”
The pioneer Phoenix builder’s interest in solar energy took its first concrete form back in 1978 when Long, in a joint venture with Arizona State University, the Department of Energy, the Massachusetts Institute of Technology and other interested parties, built his first, free-standing, demonstration model of an all-solar home.
“But,” he said, “the panels were roof-mounted and it had too many limitations--principally from the design standpoint. The appearance was poor, particularly if the house were facing south, which meant that the panels all had to be in the front.
“So then, after a couple of years, we tried it with the panels mounted on a free-standing tracker and thought seriously, for awhile, about not being gridded into the utility--generating the energy, instead, and using batteries for storage. But, with a tracker following the sun across the sky, there was the constant danger of a break-down. There were simply too many moving parts and it, too, was both expensive and unsightly--30 feet high, in fact. And then we gave up on the storage idea because battery technology hasn’t kept pace with photovoltaic technology--at least in terms of price.”
But why go to the expense of individual input/output meters for the homes? Why not simply co-mingle the collective energy generated by the housing development and pool it with the Salt River Project?
Long smiles. “It wouldn’t have the dramatic impact,” he explains. “These people who have already bought into Solar 1 want to see how the system works for them . They want to thumb their noses, individually, at the utility--to feel independent of it.
“Frankly, I think the days of the big generation centers have had their day. What we’re doing here is laying the groundwork for the day of the mini-utility.”
