While homeownership in a state dominated by cloudless skies, blazing sunshine and frozen margarita-ready temps can be lovely and all, a sun-drenched climate doesn't always translate to savings in the rooftop photovoltaic department. Among the best states — and by best we mean easiest and most financially advantageous — for residential solar installations are in parts of the country where the weather could best be described as cruddy, stormy, rainy, dismal, mercurial and all-around unbearable.

We’re looking at you, New York and New England.

In its 2015 State Solar Panel Rankings Report, solar advocacy group Solar Power Rocks has doled out letter grades to all 50 states — and Washington, D.C. — based on a complex set of criteria including payback time, renewable energy policies, available incentives to homeowners and the long-term health and well-being of solar power in each state.

With New York and Massachusetts both scoring A+ grades and Connecticut, New Jersey and Vermont each achieving a solid A, it’s obvious that sunshine-y weather has little to do with the money-saving, CO2-slashing appeal of solar power. After all, how else can you explain the Sunshine State itself, Florida, scoring a C grade?

In the 2015 edition of Solar Power Rocks’ annual rankings, a dozen states flunked out of Residential Solar 101 including Georgia (“the best of the lousiest”), North Dakota (“you can’t frack your way out of this, NoDak”), Alabama (“another state with plenty of sun that fails at promoting clean, renewable solar power”) and, at the bottom of the barrel, Idaho, which dropped four spots from last year to come in dead last.

Ouch.

Oklahoma had the dubious distinction of being the worst state in the nation for residential solar in last year's state-by-state rankings published by Solar Power Rocks. This year, Oklahoma crawled up the list slightly, ranking 49 out of 51. Obviously, lawmakers in the Sooner State better act post haste if they ever want to free themselves from being considered one of the most abysmal places in the U.S. for homeowners to invest in solar.

The secret's in the scorecard

So what did these states do wrong and the aforementioned states in the Northeast do right on their respective solar power report cards?

In ranking each state, Solar Power Rocks scored each state by an array of criteria falling under three main categories: Legislative Policy (renewable portfolio standard or RPS, electricity cost, RPS solar carve-out), Incentives (solar rebates, solar tax credits, performance payments, property/sales tax incentives) and Solar Accessibility (net metering, interconnection). Internal rate of return, the length of purchase payback and whether or not a state allows for solar leasing also factored into the overall grades.

While sun-blessed but middle-of-the road performers such as Arizona (19) and Hawaii (17) might have achieved high marks in some categories, shoddy scores in other categories landed them in solid B territory. For example, Hawaii, up one spot from last year, received As in both solar tax credits and average electricity cost (it’s high) but was hindered by low grades in solar rebates, sales tax exemptions, performance payments and interconnection (the ease of getting solar panels connected to the power grid).

solar panels on a roofThe most dramatic positive switch-ups from the 2014 rankings include Connecticut (up 10 spots to No. 3 on the list), Rhode Island (a sizable leap from 35 to 20), 16th-placer Wisconsin (a total forward jump of 12 spots) and Minnesota, a state that held the 22nd spot in 2014 and, in 2015, forced its way into the top 10 with an eighth-place ranking. Impressive!

Writes Solar Panel Rocks of Minnesota’s upward trend:

Minnesota is the biggest gainer in our solar power rankings this year, shooting up 14 spots even as its largest utility transitions from a rebate program to a performance payment. The incentives are still good, though, and Minnesota’s RPS and solar carve-out are some of the best in the nation. Way to go, North Star!
States that exhibited a sizable, nothing-to-be-proud-of descent from 2014 to 2015 include Illinois, which fell 12 spots from 10th place to the 22nd slot; North Carolina, down 11 spots to 25th place; and Arizona. As mentioned, Arizona ranks numero 19 on 2015's list, a solid 12-spot drop from 2014. The biggest decline, however, belongs to Pennsylvania, which plummeted 17 spots from solid B territory to a D-earning ranking of 34. Solar Power Rocks attributes the drop to a “weak RPS” along with “disappearing solar rebates and a languishing SREC market.”

In addition to New York, Massachusetts, Connecticut, Minnesota, New Jersey and Vermont, other states that stayed put — or moved into — the top 10 include Oregon, Colorado and New Mexico. Maryland, which despite a five-spot drop from the hallowed second place spot, also remains in the top 10.

And how'd California, a progressive, renewables-embracing state that's home to not one but two cities that now require solar panels to be installed on all newly built single-family residences, rank in 2015?

Not budging from A territory, the Golden State held firmly on to its 12th-best-state-for-solar ranking. Explains Solar Power Rocks: "With one of the best and earliest RPS laws in the country, it has done more than any other state to promote solar energy. In fact, solar has done so well here that some of the amazing rebate offers of the past have gone away, but California still earns a spot near the top ten for its excellent policy, incentives, and accessibility rules." 

Along with California, Delaware and Washington, D.C., both received A grades but failed to crack the top 10 in 2015 as they had in previous years. 

How’d your own state fare in the 2015 rankings? 

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Photo: ER_90/Shutterstock

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.