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In that location are a lot of great reasons to install solar panels. We're not going to embrace all the pros and cons in this article, but if yous have decided to go forward or are looking for tools to help you make that decision, we offering some difficult-earned lessons from our ain experiences, and those of many others over the years, that tin can help brand your project a success.

Doing Your Ain Financial Analysis

Based on extensive experience I can pretty much guarantee that when you contact a solar company to get an estimate, information technology will include a pitch to nil out your electric bill and a fancy, graphically enhanced analysis showing that you will salve a zillion dollars over some hereafter catamenia. My first problem with that is there is no reason to believe zeroing out your electric bill is the right corporeality of solar to install. Certain, it is an obvious goal, and the style net metering works may give you the about savings. Merely you might also want to beginning with a cash upkeep, or an area of your roof yous're willing to deploy, or some other projection size you'd prefer. So you lot may accept to button back a bit and get a quote for the size of the arrangement you desire.

Similarly, while the payback projections often wait awesome, they come with lots of assumptions. Commencement, they assume a certain annual productivity for your panels. If the visitor hasn't been on your roof (or on your site if you have a solar field planned) to evaluate shading, take their initial analysis with a grain of salt. Google Globe is amazing, but as the virtually common tool used by solar sales teams, it is but an approximation.

According to this cheery proposal I can save 127K by dropping some money on solar now. However, lots of tricky assumptions go into the numbers you get in a solar proposal, so best to do your own homework

According to this cheery proposal, I can relieve $127K past dropping some coin on solar now. However, lots of tricky assumptions go into the numbers you lot get in a solar proposal, so all-time to exercise your own homework

Each solar company has its ain assumptions well-nigh both productivity and the projected rate of electric utility cost increases. One of them might even be right, merely you can easily be comparison apples and oranges if different bidders on your projection take unlike assumptions. I highly recommend building your own simple spreadsheet based on the kilowatts each vendor bids and the total cost, along with federal and other revenue enhancement credits you lot might qualify for, likewise every bit your boilerplate cost of electricity. If you are really gung-ho, yous tin endeavor to adjust for time of twenty-four hour period and accommodate the effects of Time Of Use (TOU) metering that you'll probably get with solar, just that can exist a daunting task.

Similarly, I'd exist skeptical of the estimates for increases in electric rates. Specially since many bids don't allow for the involvement y'all could earn on the money you lot put into solar if yous were just paying your electrical bill and banking the rest of the coin. Then I merely use our current electric bill and get a uncomplicated payback period by dividing the net cost (after tax credit) of the system by the price of the electricity it generates (KW installed times an efficiency number we'll discuss further downwards, divided by a composite utility cost per KWH).

Figuring out your Solar Efficiency Using Projection Sunroof

Fortunately, at that place's an piece of cake-to-apply, free tool for estimating your potential solar output — Google's Project Sunroof. It uses a model of your roof and the elevation of surrounding copse from Google's World dataset and combines it with typical almanac weather to spit out an expected number of KWH per yr. It is definitely not perfect, every bit roof size and tree height estimates aren't always spot on, but it gives you a great sense of what you lot might look. Even better, it volition do a quick cost adding that takes into account the probable retail cost, Federal Tax Credit, potential state and local credits, and other benefits. Project Sunroof uses a reasonable ii.ii percent estimated inflation rate for your utility bill, and 4 percent discounting for calculating Internet Present Value, both of which are nicely bourgeois.

If forward-thinking Thomas Jefferson was alive today, Project Sunroof calculates he could save $30K over the coming years with a massive 21.5KW solar array on the roof of Monticello.

If forward-thinking Thomas Jefferson was alive today, Project Sunroof calculates he could relieve $30K over the coming years with a massive 21.5KW solar array on the roof of Monticello.

In our particular situation, nosotros're pretty lucky as we go lots of sun and accept an unshaded roof. Projection Sunroof estimates that we get just over 1,800 hours of "elevation solar" (times when 1000 watts per square meter of solar radiation are hitting our roof) each yr. So each KW installed will generate close to 1800 KWH per year. There are inefficiencies in the arrangement, of course, but they are quite a bit smaller than when nosotros installed our initial solar array 15 years ago. As far as calculating savings, the next stride is to model your utility rates. Our utility rates are massive, something like $.30 composite per KWH (even with TOU metering). And then overall, each KW installed is worth between $500 and $600 per twelvemonth

Project Sunroof does a fairly good task of estimating your electric rates, based on public databases. Once you've given information technology all the facts, it will spit out an average cost for a solar install of the size you specify in your area, along with estimated savings on your electric pecker. My one gripe with Project Sunroof is that these numbers are subconscious, and I don't see any way you tin supply your actual electric rates or bids from contractors.

Project Sunroof is hardly infallible. It would have told Thomas Edison that he could only install a paltry 176 square feet of solar panels, despite his sprawling set of lab buildings

Project Sunroof is hardly infallible. It would have told Thomas Edison that he could simply install a paltry 176 foursquare feet of solar panels, despite his sprawling prepare of lab buildings.

In our case nosotros're in a high-cost area (Northern California) with a big demand for solar, so bids tend to exist premium priced — between $3 and $4 per watt, depending on the roof, installation size, etc. That ways that using my simple spreadsheet, and the data from a number of quotes for houses in our area, payback is between 5 and seven years, with some very-high-end installers bids coming in with paybacks equally long as 9 years. My numbers were a pretty good lucifer with the unproblematic estimates provided by Project Sunroof. Hither again, it'due south up to you whether the effect is a good investment financially for you, or simply something y'all want to do, or too much of a hassle. That's your call.

Keep in listen that unusual roof configurations or specialty roof surfaces like tile can likewise cost more. Speaking of roofs, in many cases installers won't put panels on forest shake roofs, and it doesn't make too much sense to put a large assortment of panels on a roof yous'll be replacing soon. So you may want to expect for a visitor that can have full responsibility for both your solar and your covering work.

Going Solar May Toll Less Than You Recall

Some others on the ExtremeTech staff live back East and are skeptical that solar would pay off for them. Nevertheless, it is absolutely worth checking, every bit some states, and some utilities, have adequately large credits bachelor — in some cases as large equally the nationwide 30 percent Federal Revenue enhancement Credit — while here in California, most of the credit money has stale up.

For instance, fortunately for the late Thomas Alva Edison, he would exist in an area (Northern New Jersey) that has additional credits available for solar installs:

Project Sunroof does notice the Edison would be eligible for additional credits based on his lab's location.

Projection Sunroof does discover the Edison would exist eligible for additional credits based on his lab's location.

Placing and Selecting Panels

One of the biggest surprises for me when working out where to put panels is that the verbal bending on which they are placed isn't extremely critical. If your roof is inclined at all, having them flat on the roof is a depression-profile mode to go. Similarly, if your roof is somewhere betwixt Southeast and Southwest, it is probably close enough so that trying to angle the roof-height panels another direction is probably not worth it.

While we're on the discipline, at that place are a couple of solar roof options slowly emerging. Tesla is horribly behind schedule and much more expensive than the visitor lets on, but at some point might be competitive. Similarly, DuPont has licensed v3 of its solar roof shingles to Real Goods, every bit RGS Powerhouse. They look really promising and if you tin can wait a year might be a expert option. But they are notwithstanding in such an early stage that they haven't even responded to my emails to get on their early interest list.

As to selecting panels, the adept news is in that location are a lot of corking options. Even the tariffs haven't slowed things downwards, as they don't increase the full project cost as well much and there are enough of panels made other places than mainland China. If you're worried about looks, get panels that are all black. If y'all have limited roof space, paying more for maximum efficiency panels might be worth it. Other than that, make sure it is a reputable vendor with a great warranty.

Fortunately, there are loads of sites with detailed information on all the various products. Friends of mine who are toll sensitive but take lots of space on their roof are currently partial to the Canadian Solar panels. Panasonic, LG and specially SunPower are top-rated brands for about residential projects, with SunPower beingness the most efficient. The company we used 15-years ago, Astropower, became function of GE, that shut down their solar panel unit shortly thereafter. For our electric current project, we're going with G5 Hanwha Q.Cell panels. We got a skillful price on them and Hanwha is a well-respected console vendor worldwide, and are an up and comer in the US market. The G5 panels, in item, accept expert efficiency. Length of warranty may as well be important to y'all, so that is something else to add into your comparison.

Two of my own favorites are EnergySage and Existent Goods Solar. Energy Sage tin tie you lot into quotes from installers, and Existent Goods will sell you entire DIY systems, simply separate from that they both provide a wealth of information (which is all I've used them for, and I don't take whatever connection to them).

A Short Class on Inverters and Batteries

You won't learn about of this from your solar sales rep, so here it is as a public service. In that location are basically three ways to architect your residential solar. The commencement, and trendiest, is using panels with integrated micro-inverters. Each console in these systems converts sunlight all the style to AC, ready to power your house or push back onto the grid. They take the advantage that every cell is dissever, so losing one panel leaves the rest intact. Enphase seems to exist the leader in this segment. The downsides can be the cost (non cheap) and they don't integrate with backup batteries.

The second option is something like Solar Edge, which has power optimizers on each panel, giving you the benefit of having each panel isolated — and so a shaded panel doesn't mess up the system — but the organization tin can also be used with a backup battery like the Powerwall from Tesla or the LG Residential.

Finally, you can utilize a traditional string inverter. That is the lowest toll, but if ane panel is shaded or defective, the whole string tin can exist compromised. To be honest, no 1 in our area even wants to talk virtually those, but in that location are enough around in more remote locations. In our instance, nosotros have a xv-yr-old Trace/Xantrex cord inverter on our older solar install that is notwithstanding chugging forth. Every bit office of our current project, it will get re-purposed to a remote location where it tin exist re-used.

On batteries, unless you can notice someone who will work with a archetype inverter like an Outback or a bombardment system add-on like offered by Schneider, you may not be able to employ traditional price-effective solutions similar AGM lead-acid batteries. All the installers I've contacted recently only want to use the newer, and much more expensive, Lithium-Ion batteries. None wanted to even await at our existing AGM battery banking company. The new batteries are a much improve product once you buy them, and can exist used for time-shifting power to arbitrage TOU metering, but they tend to get-go at $10K and upwards installed price. I suspect that will showtime to change fairly soon, every bit higher-volumes help reduce prices, but correct now even at the current prices, all the whole home batteries are difficult to notice or back ordered. Annotation that LG makes units smaller than the 10KWH version you can currently purchase here, but they aren't sold in the US however.

Credit: Getty Images

Selection a Reputable Solar Visitor That Can Practise What You Need

If y'all are in an area that gets a lot of lord's day or has cracking rebates on solar, you're probably deluged with ads for solar companies. They are admittedly, definitely, non created equal. Exercise your own research on them. Yelp is an obvious place to starting time, as is the Better Business Bureau website. If your town has some type of customs mailing list or forum, reach out and ask. Compare notes with others going through the process. There are sites similar solarreviews.com where you can come across a variety of installers and their ratings, merely I'd never trust a single site, as it is hard to know what their bias is, how they treat companies depending on sponsorship, etc. Every visitor will take a few one-star reviews, but if y'all read them and they have a agonizing theme or seem to apply to your state of affairs, y'all may desire to steer clear.

You lot'll also want to brand sure that your choice can practice that work yous demand. Do they accept a reputation for taking intendance of expensive tile roofs? Tin they work within tight deadlines? Are their output estimates accurate? Tin they also exercise any re-roofing you need and project manage the entire effort? Are they probable to be in business when yous need to look them up in 10 or 20 years to fix something? Everyone'southward priorities are unlike, so call up about your own every bit you evaluate.

Locally, we found 3 companies that met our needs: Cobalt Ability, Semper Solaris, and Ilum Solar. Our option betwixt them is an example of how each project is different. Cobalt doesn't accept its own roofers and nosotros needed covering. They also tend to be quite pricey. Semper gave us a solid estimate, only from our initial contact, we just didn't have confidence that they actually understood our overall project and needs. Ilum Solar offered roofing, solar, and some pretty-serious technical project staff that have been available to sort through bug on panel placement, inverter option, and overall arrangement pattern while we work with their sales team.

Stay Tuned for Part 2 as Nosotros Roll Out Our Projection

Having done solar projects myself previously, documented how similar projects went for friends, and researched results of many neighbors' and colleagues' efforts, the advice nosotros have provided here has definitely been tested in the existent world. But we've got some other test coming upwards: deployment of our current 7.five KW system. It'll be unfolding over the next couple months, and we'll be back with an update on how it works out. Stay tuned. In the concurrently, since experiences vary wildly based on where you are in the state and your budget and priorities, delight let usa know almost your experiences in the comments.

Update: Going Solar Part 2: Ensuring the Project Is a Success

At present Read: California's new solar power found is actually a death ray that'due south incinerating birds mid-flight, Tesla Will Sell its Powerwall and Solar Roof in Dwelling Depot, and Solar Roads Officially Suck.

Top image credit: Getty Images