88 In Practice that are predictable, our solar resource is consumers can input some basic infor- the most predictable thing we’ve got.« The mation about their system and get back National Renewable Energy Laboratory an estimate, complete with irradiation (NREL) has thirty years of irradiation sta- estimates, incentives, and savings data. tistics for the entire U.S., and you can check These can help you check whether your the local averages against your installer’s as- installer is way off target. sumptions. But if an installer won’t guaran- Scott Cronk, who runs Solar-estimate. tee system yield within 5 to 10 percent of org – one site that offers an online solar the estimated yield for your area’s irradia- estimator for the entire U.S. – says that tion levels, it has nothing to do with the customer feedback on the installer re- amount of sun at your location. Once you have all your expectations in order, Brooks recommends obtaining an independent meter that measures and records you’re your system’s energy yield. Inverters can malfunction, taking this data with them, and even paid online monitoring systems can fail sometimes. Installing a meter that measures and stored system output, will help you know if you’re getting what you were promised. views on his site is mainly pretty positive. (7.) Money matters He says that when problems do arise, they often result from confusion about money. Most installers, and especially the es- Either there is a misunderstanding about tablished ones, will include fi nancial in- the way incentives work, or a supply formation in their proposals. Figures such chain issue on the installer’s side means as cash-fl ow analysis, levelized cost of the customer has to pay for a system that electricity, payback time, and savings esti- hasn’t been installed yet. Ideally, installmates can be informative, but don’t forget ers should educate their customers about their source: the installer. It’s important incentives, but learning on your own is to confi rm these fi gures and decide for a good precaution. The online Database yourself if the investment makes sense for of State Incentives for Renewables & Ef- you. Keep in mind, every forward-looking fi ciencies (DSIRE), run by the North Car- fi nancial analysis includes assumptions olina Solar Center, is an excellent, up-to – things like infl ation and estimated in- date resource on federal, state, and local creases in energy bills. Find out what your incentives – and how they work. installer’s assumptions are, and where they got them, says Brooks, and then run (8.) Arranging the drop them through a »reality check.« Once you’ve decided which proposal There are several tools online where best meets your needs, there is one thing that absolutely Reality check! Plug in your system details online for a free evaluation at: must be defi ned in the contract, says Free estimate web sites Brooks: how much www.pvcalc.com you have to pay, www.solar-estimate.org and when. »It’s true www.fi ndsolar.com/index.php?page=rightforme of all contracting,« www.consumerenergycenter.org/renewables/estimator/index.html (California only) Brooks adds, »as a nyserda.cleanpowerestimator.com/nyserda.htm (New York only) www.pvwatts.org (for advanced users) consumer you don’t want to get yourself Company-hosted web sites (powered by Clean Power Research) in a position where www.sunwize.com/calculator/solar-system-calculator.php it’s more advanta- www.kyocerasolar.com/products/pv_calculator.html geous for the in- ıı staller to walk.« In other words, until the system is up and running, it’s a good idea to hold on to enough of the money to incentivize the installer to stay around. Brooks says that a customer should expect to pay a down payment, or »earnest money,« of about 5 percent, or $1000, whichever is larger, when signing the contract. Around 50 percent should be paid on delivery of the equipment, he says, and the customer should always hold on to at least 10 percent One thing that really should be standard is a guarantee that the system will produce within the estimated yearly yield in kWh. until the system is connected to the grid. Absolutely never pay the full amount before the system is up and running. »That’s pretty much guaranteeing that you’ll never get it turned on,« says Brooks. (9.) After the fact Beyond money, one of the biggest problems consumers complain about in their online reviews, says Cronk, is aftersales support. And this takes us back to the fundamental need to review your proposals carefully. Make sure your installer is reputable before you sign, do your research, and ask questions. »I see all too often that consumers are lazy,« says Brooks, who insists that a customer that only gets one bid is testing fate. And, indeed, there are a number of readily accessible resources that can help you get the right bid, with an installer that you can trust will not to walk away after the contract is signed. Go Solar California’s website is one source where you’ll fi nd everything from PV technology basics to a user handbook for purchasing a PV system. The National Renewable Energy Laboratory’s (NREL) website also offers great resources and links. It may seem like a lot to learn, but, as with any long-term investment, doing your homework will pay off in the end. Melissa Bosworth November 2009
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A LONG, STRANGE TRIP SOUTHERN EXPOS
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