Solar power for less than $500
Here are five ways to start using solar power without spending tens of thousands of dollars.
Mon, Apr 26, 2010 at 02:50 PM
Ah, the dilemma of solar power: so clean, so abundant — and so expensive.
There's no end to the potential of solar power. The amount of solar radiation reaching our planet's surface in any given hour is theoretically adequate to meet all of humanity's current energy needs. That sounds great, and huge strides are being made to bring residential solar power down to the level where it can be an affordable option for people other than Silicon Valley CEOs and well-heeled eco celebrities.
But for most of us, solar power is still a fairly daunting investment. Even if you're in a position to finance a major home improvement project and live in an area that offers tax subsidies for solar investment, a system capable of covering your home's current energy use will run into the tens of thousands of dollars. This assumes you're a homeowner. Tough economic times and an unstable housing market have more Americans renting than ever before, and none of these people are candidates for a solar retrofit.
And so we wait ...
The good news is this: the future is solar. Photovoltaic panels continue to get smaller, cheaper and more efficient. Installation costs are declining in direct proportion to the number of solar systems going into the field. Policymarkers are waking to the benefits of a more decentralized power grid, and community building codes increasingly reflect the new reality of solarized homes and businesses.
Solar power is on its way. In the meantime, how can we use all these free photons? It depends on your needs and budget, of course. But we've rounded up five ways you can start using solar energy today.
Our ground rules are pretty simple. Each of these mini solar investments must provide reasonable benefits, not be more involved than a weekend project, and clock in under $500. They're not restricted to photovoltaic conversion, and may use solar energy in any way. Both DIY projects and product purchases are fair game.
Ready to give it a shot? Pick one, and join the solar age!
Small-scale solar panels
When most people think about solar power, the first thing that comes to mind is solar PV (photovoltaic). These are systems that convert sunlight into electricity. The size of the installation can vary, but it will have three basic components: panels, which capture sunlight and convert it to electrical energy; a controller, designed to prevent overcharging; and some sort of storage battery. Many systems will also have a DC to AC power converter.
For $500, you can't buy enough juice to run a major appliance, much less an entire home. But if you're willing to do the work yourself, you can afford the materials for a self-contained system that will provide enough clean, renewable power for small electronic devices and chargers. Small-scale solar is useful for emergencies, too. You'll be able to run a laptop or keep your cell phone charged, even when your neighbors are sitting in the dark.
Sunforce is one of the many green companies providing consumer-level solar power kits and components. Their 50044 60-Watt Solar Charging Kit retails for about $600, but can be found on sale through places such as Amazon for about $300. That leaves a couple hundred bucks for a storage battery, which is not included. You're otherwise good to go, with four 15-watt panels, a frame, and most of the goodies you'll need to get up and running. Small systems like this are also great for powering things that might be impossible or prohibitively expensive to connect to commercial mains: water pumps, marine electronics — even electric fences.
Energy-efficient lighting isn't all about CFLs and LEDs. The next time you're in an older home — one constructed before electricity was common — notice the windows.
Until the turn of the last century, buildings relied on natural daytime lighting. Floor-to-ceiling windows were common (and used for both ventilation and illumination). We don't build that way anymore, but it's possible to make direct use of solar power through the installation of skylights.
Conventional skylighting can be pricey, and usually requires professional installation. But tubular skylights are a simple and inexpensive way to bring light into your living space. These consist of three basic parts: a dome collector, which is mounted above the roofline; piping, which directs the collected sunlight; and a diffuser, mounted much in the manner of a traditional roof lighting fixture.
Tubular skylight projects generally don't require building permits, can be knocked out in a few hours with common tools, and don't displace much attic insulation. The amount of light they produce can be considerable. This 18-inch kit provides the equivalent of 750 watts of incandescent light for about $400, including optional accessories. That leaves $100 to rent whatever extra tools you might need — and to buy a case of beer for whoever you can talk into spending an afternoon on the roof with you.
A humble clothesline
Here's another example of direct solar power: a clothesline. In terms of home energy use, the clothes dryer is among the hungriest of appliances, ranking immediately behind the refrigerator, climate control, hot water heaters and lighting. Depending on how much laundry you go through and local power rates, an electric clothes dryer can easily account for $200 of your annual energy use.
The sun is ready to save this money for you. A clothesline can be as simple as a piece of nylon rope tied to an apartment balcony, or as deluxe as a folding aluminum frame parallel line capable of hanging a couple of big washer loads at once. Free-standing frame units require a concrete base, so you'll need a sack of gravel (for drainage) and some Quikrete. Follow the directions supplied with the kit, and be sure to use a level to get everything is lined-up before the concrete cures.
The whole project should come in well under $100. Take the other $400 and enjoy a weekend at the beach. (Solar power works well for tanning, too.)
Solar attic fans
On sunny days, your attic can become an enormous heat trap. With temperatures of up to 150 degrees, this trapped heat will radiate into living spaces below. That means a greater demand on your air conditioner.
Take a load off by installing a solar powered attic fan. The brilliant part about solar fans is that they provide peak ventilation during the hottest, brightest part of the day. And there's no need to run wiring: Many solar fans are available with a small set of PV panel right on the top.
This fan kit is powered by a 20 watt PV array, and operates at 1,200 cubic feet per minute. That should be enough to fully vent an attic of up to 1,800 square feet. A properly vented attic can lower room temperatures by as much as 10 degrees, and a cooler roof will also extend the life of its shingles. The unit we've linked here retails for less than $450 and can be installed in an afternoon with common tools. Go with the optional thermal snap switch for fire safety. This project should pay for itself in its first year.
Who doesn't love a summer cookout? Of course, like most good things, there are downsides: VOCs (volatile organic compounds) from charcoal starter, and a none-too-light carbon footprint.
Solar cookers are another direct use of solar power. They're amazingly simple devices, utilizing one or more reflectors and a sealed cooking compartment. Relief agencies have made extensive use of solar cookers in the wake of the Haiti earthquake, due to their low cost and ease of construction. Chelsea Green has a great set of directions on how to make your own for no more than a few dollars.
If you don't want to go to the trouble — or you'd just enjoy the convenience of a well-engineered portable cooker — Sun BD sells a nifty unit it claims will produce temperatures of up to 400 degrees. That's plenty hot enough to roast meat or vegetables, bake or boil water. It folds up like a suitcase, making it handy for camping or weekend picnics. You can grab the Tulsi-Hybrid Cooking Oven for less than $250 at Amazon.
What can you add to this list?
We've started the conversation with five meaningful solar projects for less than $500 each. Can you think of others? Share them in our comments section below.
Chris Baskind is a carfree environmental writer, and the founding editor of Lighter Footstep (now part of the MNN family). You can find more alternative energy stories on our Facebook page, or via our Twitter feed.
Also on MNN: If you're solar-obsessed, you'll love this gallery from the 2009 Solar Decathlon