Solar Solutions

1 / 3
Wind pumps sweet Ogallala water, and PV-generated electricity powers the fence on this remote Nebraska cattle ranch.
2 / 3
The flexible peel-and-stick solar (photovoltaic) film installation supplies roughly half the electricity for Cheryl Long's Kansas farm.
3 / 3

When building contractor Gerald Whipple moved to southern Utah more than a decade ago, he found the perfect piece of property – 20 peaceful acres, 20 miles from town. The only problem was that his land was three miles from the nearest power line, and the utility wanted more than $125,000 to connect his new home to the grid. That’s when he decided to harness the sun. As Whipple quickly discovered, solar is a cost-effective solution for powering rural homes, agricultural buildings and equipment, and not only for landowners living far from existing power lines but also for those living where electric rates are high.

“The upfront cost is the biggest drawback to renewable energy,” Whipple says. But as fuel and electric rates continue to climb and more state and federal grants and tax credits for renewable energy become available, solar power makes financial sense. Whipple discovered such high demand for renewable energy in the American West that he founded his own consulting business, Solar Unlimited. In a typical year, his company installs 75 to 80 solar systems for varied uses on rural land throughout southern Utah, and most of his business is from clients who want to be off the grid. 

Passive harvest

One of the easiest and least expensive ways to make use of the sun’s energy is through passive solar building design. By simply orienting the long axis of a structure to face south, and installing as many south-facing windows as possible, the building can take in the warmth of the sun on cold winter days. Since the sun is farther north in the summer, carefully designed roof overhangs will shade the windows during the hottest months. In climates with mild winters, passive solar gain can easily provide all the heat and most of the light for a well-designed structure during the day. Keeping the house warm at night typically relies on insulated blinds and re-radiation from large masses in the house (such as masonry walls) that absorb excess heat during the day.

In addition to passive solar design, Whipple uses photovoltaic (PV) panels to generate electricity. Photovoltaic panels convert a portion of the energy in sunlight to direct current (DC) electricity, which can then be stored in batteries for future use. An inverter converts the DC power to alternating current (AC) for use in the home or elsewhere on the farm.

Tom Kimbis, acting program manager with the U.S. Department of Energy’s Solar Program, says that PV panel technology has changed very little over the years. Most are still silicon based with some progress in efficiency and overall thickness of the panels. The technology is still reasonably expensive, although prices are dropping because demand has allowed some manufacturing scale up.

Since much of the cost of installing a PV system relates to installation, thin film solar laminates might make more sense than rigid glass-coated panels because they’re easier and, therefore, faster to install on a large scale. Static installations capture about 60 percent of the sunlight and are considerably less expensive than the dynamic systems that track the sun throughout the day.

During the day, Whipple’s home is heated and powered entirely by the sun, and, when it comes to electricity, his system generates more than is consumed.

The considerable daily electrical excess is stored in a bank of maintenance-free gel cell batteries, which are completely sealed and have no corrosion-prone terminals. Whipple says the high-tech batteries can last as long as 15 to 20 years, while PV panels typically have a life expectancy of 50 years with virtually no maintenance. Whipple expects his entire system to pay for itself in 10 to 15 years.

Grabbing the grid

Since the vast majority of rural North America is already tied into the grid, one might wonder whether there’s any advantage to using solar technology in retrofitting an existing structure or building new. In both cases, the answer is yes. Passive solar heating design can reduce your dependence on both electricity and fossil fuels and will save you money in the long run no matter what fuels your primary heating system. But you can shave your energy bills even further with PV technology even if you are already plugged in.

It’s relatively easy to install a photovoltaic system on a farm that’s tied into the grid. Instead of using batteries to store excess electricity, you can rely on your provider. In some regions, power companies offer net metering programs where farmers get rebates for the electricity they pump into the grid. Alternatively, PV-generated power suppliers can sometimes credit their excess kilowatts against a current bill assuming they use more electricity than they generate.

Typically, the utility will base the credit on the lowest wholesale price, while charging full retail. Check with your local utility, county or state to find out what the rules are in your area.

Spirit of competition

Whipple says his company often bids against the local electric company for powering newly constructed buildings. The average home, he says, can generate all the electricity it needs with solar or a solar/wind combination for as little as $40,000 upfront investment. Whipple is realistic, though, and knows solar isn’t cost effective for all electric applications. “When you get into electric heat, it doesn’t work,” he says. “I push solar only when it makes economic sense.”

Working with water

Kimbis says solar is especially good for pumping water in remote areas. He points to the Hirsch Ranch near Racetrack, Montana, where a solar-powered pumping system uses a passive tracking rack and two 64-watt PV modules to provide up to 2,800 gallons of water per day for cattle. It cost Rick and Pam Hirsch $2,400 to install the solar system. “How much you save depends on the replacement fuel,” Kimbis says. “If you’re remote, that fuel is going to be diesel.” Diesel is expensive; plus, there’s transportation involved in getting it to the site, not to mention the noise involved in operating a diesel-powered generator. “Diesel is really dirty, too,” Kimbis says. “It’s hard to get cleaner than a PV panel.”

The most popular use of solar energy today is to heat water directly. Sun-powered water heaters can be as simple as a barrel or bladder painted black. Fill the vessel with water, place it in the sun and there you go. More sophisticated, and arguably more useful, solar water heaters make use of collectors consisting of metal tubing fused to a metal plate (painted black) that’s enclosed in an insulated and clear-glazed box. Sun energy penetrates the glazing and is transferred to water (oil or an antifreeze solution are also used) flowing through the tubes via the heated metal plate. While a solar hot water heater sized for a home can cost anywhere from $4,000 to $7,000, long-term savings can be substantial even in the northern states.

Kimbis says one can expect a four- to six-year payback on a solar hot water heater. They can also be retrofitted into an existing water heating system. “It’s an easy way to offset costs,” Kimbis says. “Farmers use a lot of warm water for cleaning and in dairy operations.” Heating water can account for as much as 40 percent of the energy used on a dairy farm. 

Why solar makes sense

The economics of solar power on the farm vary from place to place. “A lot depends on where your farm is located,” Kimbis says, “because solar radiation is better in some places than in others, and tax incentives are different in each state.”

For example, Utah, where Whipple resides, offers tax credits up to $2,000 for residential solar installations. The federal government also offers a $2,000 tax credit. Farmers who make 50 percent or more of their income from agricultural endeavors can also apply for renewable energy installation grants offered by the U.S. Department of Agriculture. Since the introduction of its Energy Efficiency and Renewable Energy Improvements Program in 2002, the USDA has granted more than $2 million to help start rural solar projects in 20 states.

Kimbis says the DOE’s goal is to have solar electricity reach parity with the grid by 2015, which is a pretty aggressive goal. In some areas such as California, solar is already cost competitive thanks to rebates available there. “If you have high electric rates,” he says, “solar is going to be an attractive option.”

Even if the solar choice doesn’t make immediate economic sense, it could make sense very soon. “People should be open-minded,” says Whipple. “The technology has come a long way, and whether or not you believe in global warming, if it’s true, it will affect us all.” As our fossil fuels become more expensive and less available, choosing renewable energy options makes sense and offers ever more independence for folks living on the land.

Deborah Huso is a freelance writer living on a 50-acre farm near Blue Grass, Virginia. She has written for several magazines and is contributing editor at Blue Ridge Country. Visit her on the Web atwww.DRHuso.com.

Renewable Energy Resources for Farmers

Published on Apr 29, 2008

Grit Magazine

Live The Good Life with GRIT!