Advancing Solar Energy in Washington State


One Block Off the Grid

Your One Stop Solar Shop
Updated: 1 hour 19 min ago

Another Benefit of Going Solar: Encouraging Others to Go Solar

Mon, 10/27/2014 - 10:56am

We talk all the time about the many benefits of home solar: You save money on your electric bill, you cut your carbon footprint, you can gain a little bit of independence from your utility company, and solar panels are just beautiful to boot.

But wait: There’s more! New research from Connecticut finds that one of the reasons that people go solar is because one or more of their neighbors have also gone solar.

It’s like the best kind of peer pressure imaginable.

The study, which appeared in the October 7 issue of the Journal of Economic Geography, bears an inscrutable title: “Spatial patterns of solar photovoltaic system adoption: the influence of neighbors and the built environment.” But the findings from Marcello Graziano of the University of Connecticut and Kenneth Gillingham of Yale University, are anything but ho-hum: “Our empirical estimation demonstrates a strong relationship between adoption and the number of nearby previously installed systems as well as built environment and policy variables.”

In other words: The biggest factor that determines whether people go solar is not their income level or their monthly electricity bill, but whether or not someone near them has already gone solar.

The full study is trapped behind a paywall, but over at the Washington Post, Chris Mooney has a rundown of the findings.

Graziano and Gillingham looked at Connecticut’s recent solar boom and used data from the state’s Clean Energy Finance and Investment Authority for 3,843 home solar installations between 2005 and 2013. Mooney explains the “dramatic findings:”

The installation of one additional solar photovoltaic rooftop project within the past six months in a given area increased the average number of installations within a half mile radius by … almost one half. As the spatial area widened, meanwhile, the influence of peer solar installations steadily decreased, a finding quite consistent with a theory of peer influence….

But while prior installations seemed to have a big influence on future ones, Graziano and Gillingham failed to find nearly as much of an influence for other socioeconomic and demographic factors. That included income, political party registration, and the unemployment rate.

Mooney notes that the researchers do also identify Connecticut’s solar incentives as a driver of the state’s solar boom. We have covered Connecticut’s use of the Solarize platform to speed solar adoption, a tool that has since expanded into more Connecticut towns.

Solarize in particular seems to be an ideal tool to leverage the peer pressure model of solar adoption. Through a Solarize program, homeowners in a town are encouraged to commit to going solar, and if enough homes make the pledge, then they all receive a discounted rate on their solar installations. These group processes then offer an active financial incentive for spreading the word about solar in addition to the passive peer pressure incentive identified in Graziano and Gillingham’s research.

Check out Chris Mooney’s full article in the Post here; he’s got a good chart and explanation of how this peer pressure effect happens independent of income levels and other demographic data. And the full article, for all of our Journal of Economic Geography subscribers, is here.

Solar neighborhood photo courtesy of SMUD and the U.S. Department of Energy.

Talk to Your Kids About Solar

Wed, 10/08/2014 - 6:56am

If you’ve got kids, you know that they are little bundles of limitless curiosity. And maybe they’ve already asked you about the solar panels they’ve seen in the neighborhood, or at school, or when you’re out shopping.

For my preschooler, the first time he asked about solar panels was when he watched the Pixar film Wall-E for about the four-hundredth time. In addition to being a sweet movie about love and environmental stewardship, Wall-E is also about a solar-powered trash-compacting robot, and my curious little kid wanted to know all about the solar panels Wall-E uses to power up his batteries.

Solar technology is obviously a complex topic, but there’s no reason you can’t talk to your kids about solar starting at almost any age.

There are a few great resources online to help you dig into the topic. Solar Energy International has created solar FAQs for younger kids as well as for older kids and adults. And the U.S. Energy Information Administration has a useful page of solar basics for kids as well.

Below are some simple ways you can start teaching kids about solar, starting today. And read on for more details about our new solar quiz and prizes you can win.

Your Inverter: The Gateway to Energy Use

The inverter in your home solar system — the box that converts the energy generated by your solar panels into the electricity that powers your home — can be a great teaching tool for a child of any age. Show your child the data the inverter presents about the amount of energy you’ve generated during the day and teach her about electricity and units of measurement.

For an older child, ask him to keep track of the daily power generated by your solar panels for a week or a month, and graph that information to see how your family uses electricity. Families that have a home energy management system in place can very easily connect your daily energy use to the output from your rooftop solar system.

A Home Solar Science Fair

There are a number of ways you can turn your home solar system into a teaching tool. For younger kids in particular, explain how the panels generate more energy at different times and under different weather conditions, and ask him to connect the day’s weather to the day’s energy generation.

Another cool project is trying to make the meter run backwards. Get your older child to gauge the effects of turning on and off various energy-using devices in the home. How much impact does turning off all the lights have? When she cranks the air-conditioning — or turns the thermostat way up — what happens to energy use?

Everyday Solar

Connecting solar power to your kids’ everyday lives is another sure-fire teaching method.

Solar-powered ovens are a great way to show just how much energy the sun offers us every day. Using a cardboard box, some spray paint and some foil, you can help your child build a solar oven in no time.

Maybe the best way to teach your kids about solar power is to show solar in action. It seems like every day there are more and more solar gadgets hitting the market and entering our lives. You probably had a solar-powered calculator when you were in school — and there are still plenty of those around — but now we’re also able to make use of portable solar panels to charge our gadgets, solar-powered lights for landscaping, and solar-powered tchotchkes of all kinds. Each of these offers a chance to help your kids understand about the power and benefits of solar energy.

And for the month of October as we prepare for Halloween, everyone who takes our new solar quiz will receive a cool Spark solar-powered flashlight from Silicon Solar. This gadget will not only help you show how solar panels work, but it will come in handy when you go trick-or-treating.

Here’s to a solar-powered October, and a sunny and spooky Halloween!

NRG Acquires Pure Energies Group

Mon, 10/06/2014 - 11:11am

NRG Energy Acquires Pure Energies Group, Adding Stronger Online Platform for Customer Access to NRG’s Rapidly Expanding Residential Solar Business

Pure Energies builds on recent acquisitions to empower customers to go solar in an easy and streamlined way

PRINCETON, N.J.–(BUSINESS WIRE)–Oct. 2, 2014– NRG Energy, Inc. (NYSE:NRG) has acquired Pure Energies Group, Inc. (Pure Energies), a residential solar industry leader in the critical area of web-based customer acquisition. Pure Energies completes the residential solar capabilities NRG has been working to assemble and perfectly complements NRG’s acquisition earlier this year of Roof Diagnostics Solar, a leader in home solar direct sales and installation, and NRG’s own Residential Solar Solutions, which has focused on the financing and business operations associated with solar leasing. All of these capabilities and operations, combined as NRG Home Solar, create a one-stop shop for prospective solar customers, offering the optimal rooftop solar system customized to their homes and needs.

Pure Energies and its proprietary customer acquisition process will help NRG Home Solar reduce customer acquisition costs while providing a simplified solar adoption process. Pure Energies’ online capabilities also are expected, ultimately, to provide a valuable sales channel for NRG’s Goal Zero line of portable solar and energy storage products and NRG’s retail businesses (NRG, Reliant and Green Mountain).

“Home solar is the gateway for most American consumers to join the growing movement toward a clean energy future, and the combination of Pure Energies’ rapid growing online footprint with our existing residential solar platform will enhance our ability to provide customers, wherever they are, the freedom to make their own clean energy and capitalize on the energy generating potential of their own home,” said David Crane, President and CEO of NRG Energy. “While residential solar is being increasingly embraced by homeowners of all ages across the United States, buying over the internet is the acquisition channel of choice in particular for the younger generation of Americans for whom commitment to a sustainable lifestyle is a fundamental part of their DNA.”

“We are focused on being a trusted energy advisor to help homeowners save money on their electricity bills while they invest in a more sustainable lifestyle,” said Zbigniew Barwicz, President of Pure Energies. “Being part of NRG Home Solar allows us to increase our abilities to support homeowners by facilitating the adoption of solar energy and home conservation products across the United States.

Pure Energies advises homeowners on residential solar systems and home conservation products to help them save money and make a difference in their communities. The company, which previously also used the One Block Off the Grid (1BOG) brand, empowers customers to make smart decisions about home solar adoption. Through a unique online platform, Pure Energies is able to, within minutes, identify and provide a detailed analysis of the customer’s home solar feasibility versus their energy needs.

“NRG strives to provide customers with the easiest path to assess the benefits of home solar,” said Kelcy Pegler Jr., President of NRG Home Solar. “With Pure Energies’ wealth of experience in connecting consumers to their full energy potential – combined with NRG’s strengths as a Fortune 250 company well-established in residential solar – consumers will have greater access to meet their solar needs. The team at Pure has experience in solar across multiple states and countries and has a demonstrated track record of success in the home solar business. Together, we will empower consumers to make smarter, better informed decisions as they move toward the clean energy economy.”

About NRG

NRG is leading a customer-driven change in the U.S. energy industry by delivering cleaner and smarter energy choices, while building on the strength of the nation’s largest and most diverse competitive power portfolio. A Fortune 250 company, we create value through reliable and efficient conventional generation while driving innovation in solar and renewable power, electric vehicle ecosystems, carbon capture technology and customer-centric energy solutions. Our retail electricity providers serve nearly 3 million residential and commercial customers throughout the country. More information is available at Connect with NRG Energy on Facebook and follow us on Twitter @nrgenergy.

NRG Safe Harbor Disclosure

This news release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Such forward-looking statements are subject to certain risks, uncertainties and assumptions and include NRG’s expectations regarding Pure Energies, NRG Home Solar and the residential solar market. Forward-looking statements typically can be identified by the use of words such as “expect,” “believe,” and similar terms. Although NRG believes that its expectations are reasonable, it can give no assurance that these expectations will prove to have been correct, and actual results may vary materially. Factors that could cause actual results to differ materially from those contemplated above include, among others, general economic conditions, hazards customary in the power industry, competition in wholesale power markets, the volatility of energy and fuel prices, failure of customers to perform under contracts, changes in the wholesale power markets, changes in government regulation of markets and of environmental emissions, and our ability to achieve the expected benefits and timing of our residential solar projects and the residential solar business. NRG undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. The foregoing review of factors that could cause NRG’s actual results to differ materially from those contemplated in the forward-looking statements included in this news release should be considered in connection with information regarding risks and uncertainties that may affect NRG’s future results included in NRG’s filings with the Securities and Exchange Commission at


Source: NRG Energy, Inc.

For NRG Energy
David Knox, 713-537-2130
Erik Linden, 609-524-4519
Chad Plotkin, 609-524-4526
Daniel Keyes, 609-524-4527

Top 10 Countries Using Solar Power

Mon, 09/15/2014 - 10:00am

Back in 2010, we researched the countries that were leading the world in solar power installations. As of the end of 2009 — the latest data we could gather — the solar industry was in the very early stages of the global solar boom that has been accelerating ever since. In the interest of taking the current pulse of the global solar leaders, we’ve updated this post in September 2014 to reflect the new state of play. We’re keep the 2009 numbers in parentheses as a reference point of just how quickly the world is switching to affordable, clean solar energy.

One telling point: The solar industry is growing so rapidly that we’ve had to update our units of measurement from megawatts (MW) to gigawatts (GW).

Below are the top 10 countries using solar power in the world according to installed photovoltaic solar (PV) energy capacity. Think you know the order? You might be surprised…see if you can name all ten countries in the right order before continuing on.

1. Germany: 35.5 GW (2010: 9.8 GW — 1st place)

In 2010, Germany was clearly the world leader, and has only continued the trend. In 2009 alone, Germany installed 3.8 GW of PV solar energy capacity, and the country has added at least 3.3 GW of new solar capacity per year, and more like 6 GW per year between 2010 and 2012. “The combination of a proven feed-in-tariff (FiT) scheme, good financing opportunities, a large availability of skilled PV companies, and a good public awareness of the PV technology, largely contributed to this success,” European Photovoltaic Industry Association (EPIA) reported.

Despite a slowdown in 2013, Germany is expected to remain the top solar market in Europe for the coming years, and still boasts a quarter of the world’s installed PV capacity 26 percent, compared to the 13 percent held by each of the next two countries on the list, Italy and China.

Image credit

2. China: 18.3 GW (2010: .305 GW — 8th Place)

Everything that China does, it does big. As the world’s most populous nation, and the one with the biggest carbon footprint, it’s great news that China has made such a major commitment to solar power. Since our 2009 research, China has grown its solar capacity by an astounding 6,000 percent — from less than one-third of a gigawatt of capacity to 18.3 GW. It helps that China is a major solar panel manufacturer, and the government has had to repeatedly raise its renewable energy targets — from a plan of 20 GW by 2020 to 20-30 GW by 2020 to the current target of an astounding 70 GW of solar by 2017. Coupled with a commitment to cut its coal use, the world’s biggest carbon polluter could soon also be the country powered with the most green energy.

Image Credit

3. Italy: 17.6 GW (2010: 1.2 GW — 5th Place)

Not only has Italy continued its leadership in solar — rising from fifth place in 2010 to third place as of the end of 2013 — it generates more of its energy from solar than any other nation, with 7.8 percent of its energy coming from solar, compared to 6.2 percent for Germany. Mixing net-metering and a well-segmented FiT (combined with a lot of sunshine), Italy has become a world leader in solar energy. “The future growth of the market will depend on the streamlining and harmonisation of administrative procedures, combined with an adapted decrease of the FIT in the third Conto Energia to cope with the expected price decrease,” the EPIA reports.

Image credit

4. Japan: 13.6 GW (2010: 2.6 GW — 3rd Place)

Japan fell from third place in 2010 to fourth place in 2014, but remains also a country worth emulating — in the past four years the country has grown its solar capacity by more than 500 percent. Government residential PV programs, net-metering, high national solar energy goals to reach 28 GW by 2020 and 53 GW by 2030, as well as the support of local authorities and the private sector make Japan a world leader in this field. In the wake of the the Fukushima Daiichi nuclear disaster, the country has renewed its dedication to solar power, particularly with the recent announcement of the first of many floating solar farms off the island nation’s coasts.

Image credit

5. United States: 12 GW (2010: 1.6 GW — 4th Place)

It’s hard to believe that a country that grew its solar capacity by 750 percent in four years could still have lost standing in the global solar boom, but that just goes to show how quickly the field is changing. The United States have benefited as much as anyone from the steadily dropping price of solar, aided by smart financing and some supportive state-level policies to grow its domestic solar industry. With many large ground-mounted solar projects in the pipeline, installed capacity in the US is expected to grow significantly in coming years. Additionally, national legislation promoting solar energy (if it comes through) could move the US forward considerably. The cap on the federal solar tax credit was lifted in 2009, promoting growth in this industry.

Image Credit

6. Spain: 5.6 GW (2010: 3.4 GW — 2nd Place)

Spain was the world leader in newly installed PV solar energy (2,605 MW) in 2008 due to the government’s focus on creating a national solar energy industry, but has since dropped significantly — between 2010 and 2013, the country didn’t even double its capacity, whereas Germany nearly quadrupled its solar capacity. The reasons for this drop are attributed to complexity and delays related to a new government subsidy program and a decrease in energy demand due to the economic crisis. With expectations that both of these will improve in 2010, and considering its excellent sun irradiation and PV potential, Spain is expected to bump up its solar energy capacity again this year.

Image Credit

7. France: 4.6 GW (2010: .272 GW — 9th Place)

France has continued to benefit from its well-designed FiT for building-integrated photovoltaics (BIPV), but the country’s solar growth has been slowed by a lack of political support for solar incentives, which the the European Photovoltaic Industry Association (EPIA) in a report published earlier in 2014 (PDF)also attributed to attacks from the nuclear and fossil fuel energy industries.

Image credit

8. Australia: 3.3 GW (2010: .125 GW [Source])

The first of two newcomers to our list of the top 10 countries using solar power, Australia has in the past five years made the most of its sun-drenched status — though its continued growth is in question. At the end of 2009, the island nation claimed only 125 MW of solar capacity, but through smart policies including feed-in tariffs, rebates and a federal mandatory renewable energy target has grown that by 2600 percent, reaching 3.3 gigawatts by the end of 2013. Between steadily dropping solar prices and the fact that Australia boasts some of the greatest solar potential in the world, solar power costs less than half what grid electricity costs, although the current government is considering scaling back the federal Renewable Energy Target, which would slow if not stop the country’s upward trajectory in these lists.

Image credit

9. Belgium: 3GW (2010: .363 GW — 7th Place)

The image above shows Belgian solar flowers. Belgium has been a surprising solar contender even since 2009. Belgium’s success was from “a well-designed Green Certificates scheme (which actually works as a Feed-in Tariff), combined with additional tax rebates and electricity self-consumption.” Those policies, coupled with the steady drop in solar panel prices, has kept Belgium growing its solar market year-over-year since 2009.

Image © Artist Alexandre Dang,

10. United Kingdom: 2.9 GW (2010: .027 GW [Source])

Another poster child for the global solar boom, the United Kingdom was nearly a no-show in our 2009 research — it didn’t make the top 10 list by a long shot, with just 27 MW of solar capacity. But it has made quick growth since then, with the EPIA noting that in 2013, the U.K. nearly doubled its solar capacity, installing more even than Italy, the current 5th-place holder.

Image credit

Off the List:

Two of the countries that made the top 10 list in 2010 have fallen behind in the rankings — we’re including them below in the hopes that they make it back on our list in the next go-round…

12. India: 2.3 GW (2010: .120 GW — 10th Place)

Similar to China, India has fast-increasing electricity demand and it has very high sun irradiation levels. It’s government has also been moving forward strongly on clean energy. It has a goal to reach 20 GW by 2020 as well. “Besides the National Solar Mission of 2009, the market expects much of the possible decision this year to define a longterm power purchase agreement that could definitively trigger PV deployment in India,” EPIA states. India could quickly rise higher on this list with proper government strategies.

Image credit

13. Czech Republic (2010: 0.47 GW — 6th Place)

A generous FiT and simple administrative procedures have put the Czech Republic on this list. Per capita, it installed more new solar power than any other country besides Germany in 2009. The market growth has probably boomed unsustainably (and a little unexpectedly), however, and if appropriate policies aren’t put in place to slow it, the nascent solar bubble is expected to bust in the coming years.

Image Credit

• 2013 figures come from the IEA Photovoltaic Power System Programme; 2009 figures via the European Photovoltaic Industry Association.

Have more to add or questions about this list? Comment below. Special thanks to Adele Peters for her contribution to this article. Sign up with PURE Home Solar for group discounts, or use our calculator to estimate the cost of solar panels for your home.

Infographic: Back to School, Sustainably

Fri, 09/12/2014 - 5:00am

Going back to school can be challenging enough without also trying to factor in the environmental impacts of your decisions. The good news is that there are a lot of little choices you can make that will make a big difference for your footprint as well as your pocketbook.

As we wind down our #smallstep for sustainability campaign, we’ve created this infographic to explore some of the ways you can go back to school, sustainably.

PURE Webinar: What Can One Person Do to Save the Planet?

Tue, 09/02/2014 - 8:54am

If you’re reading this blog, you are probably concerned about the environment — every day we’re hearing more news about the state of the climate, and how the changes that have already started happening may accelerate and get more severe soon.

As serious as the effects of climate change are, the most important things to remember are that there is still hope and the time to act is now.

To show people how their individual choices can add up to a planet-saving effort, PURE Energies has teamed up with the World Wildlife Fund to host a webinar on Tuesday, September 9. “Ideas From Outer Space: How you can affect climate change” is a one-hour conversation between Keya Chatterjee, the director of renewable energy and footprint outreach at WWF, and Chris Stern, a co-founder of PURE Energies.

Keya and Chris will be discussing some of the big challenges the world faces by looking at the small-scale steps anyone can (and should!) take to overcome those big challenges.

Among the challenges:

  • Stop coal
  • Cut all fossil fuels
  • Improve land use

Those are big challenges — and can be overwhelming to think about what it will take to overcome them.

Fortunately, there are small steps that, if everyone took even a few of them, would make it immediately possible to tackle all of these problems. And that’s exactly what’s on the agenda for our webinar.

Keya and Chris will discuss in detail some of these solutions:

• Cleaner transportation: Hybrids, electric vehicles, and a much greater reliance on public transit and bicycling are all important — and surprisingly easy ways — to reduce the footprint of your transportation needs.

• Improve your home’s energy efficiency: Starting by swapping out your energy-hogging devices — from lightbulbs to appliances — you can make a big dent in your monthly energy bill, as well as the energy needed to power your home.

• Embrace green energy: Solar power has plummeted in price by an unbelievable amount over the last 25 years. Compared to 1977, the cost of solar panels has fallen by 99 percent. But as of early 2014, solar is 60 percent cheaper than it was just three years ago. Cheaper solar plus smart financing that lets you go solar for free means that solar is a now a no-brainer.

• Join the community of people taking action on climate change. On September 21, the world is coming together in New York City for the People’s Climate March — which aims to peacefully stand up against global warming pollution and help to create a world full of clean air, good jobs and healthy communities. In every successful social movement, the single most important way to achieve change is when the people raise their voices. Even if you can’t join the march in New York City, spread the word and take action at home.

To learn more about all of these solutions, and how you can take the next step in the fight against climate change, sign up for the PURE webinar here.

Mike’s Ultimate Garage is PURE

Thu, 08/28/2014 - 2:43pm

In an effort to educate people across North America about the value of solar, PURE Energies partnered with Mike Holmes in 2013. The notion for our partnership began on the Rick Mercer Report, when Rick Mercer and Mike Holmes teamed up with PURE to install a solar array on an Oshawa home.

On September 1st, 2014, PURE Energies will be featured on Mike’s Ultimate Garage special, which airs on HGTV Canada at 8 pm EST in Canada. Viewers get an all access pass with Canada’s most trusted contractor, Mike Holmes, as he builds his dream garage. This episode will feature Mike Holmes’ PURE Energies solar installation, including 40 solar panels on the house which have a peak power production of about 10 kW. And the best part is that Mike will be handing over the white helmet to his son, Mike Jr. who will run the jobsite.

At 1850 square feet, Mike’s state-of-the-art garage will house some of the coolest gadgetry and cutting-edge solar technologies on the market.

While Mike’s popularity has guaranteed the show to air in Canada, Mike’s team is currently rallying advocates for the show to air in the US. Click here to advocate for Mike’s Ultimate Garage to air on HGTV (US).

Mike Holmes is one of the few homeowners in the PURE community with a solar array installed on his roof and on his garage. His rooftop solar array generates clean energy for his community and the solar system on his garage generates power that is used to charge his battery bank which can be used to power his home.

Tune in to Mike’s Ultimate Garage on September 1st at 8pm EST and see how Mike Holmes makes it right with PURE Energies solar.

PURE Sustainability – Take a #smallstep

Mon, 08/25/2014 - 1:45pm

Everybody knows that the real New Year starts in September. This year it is all about sustainability. What choices can we make to improve our practices as individual consumers to reduce our carbon footprint as members of a community?

At PURE Energies, we have worked with thousands of homeowners who have taken a step towards sustainability by choosing to go solar. Oftentimes, when one homeowner goes solar, many neighbors want to get in on the sunshine, and soon, an entire community has gone solar.

This school year, we want to inspire our community to think green and act sustainably!

While going solar has proven the benefits of thinking green – both for the planet and for the pocketbook – there are many other ways to be more sustainable. One #smallstep can entice an entire community to make the sustainable choice. Normally it takes one community member to take the first step towards a more sustainable lifestyle, like packing homemade lunches for their kids or carpooling, to motivate others to do the same.

To kick-off the New School Year we’re encouraging one #smallstep for sustainability. Think of one small way to be more sustainable and inspire your friends: carpool; walk to school; use reusable containers; pack organic lunches; buy used; use a solar backpack! Even if you don’t have school aged children, you can still make a #smallstep towards sustainability.

There are sustainable alternatives to most of the everyday choices we make as consumers which save the planet and save you money.

Enter your #smallstep for sustainability and be automatically entered into our contest to win 1 of 10 Voltaic solar backpacks stuffed with $500 cash!

After the first week of school we will randomly draw winners, so be sure to pledge your #smallstep before September 12th.

Ask a Solar Expert: Energy Generated by Solar Panels, Best Roof for Solar

Fri, 08/15/2014 - 6:28am

Every day, as we help people go solar and save money across North America, we get asked questions about the details of home solar. To help answer these common questions, today we’re kicking off a new series at PURE called “Ask a Solar Expert.” Our lead solar designer, George Shafer, is here to shine some light on the sometimes-confusing aspects of a solar installation.

Question: How much energy does an average solar panel produce?

Solar panels come in all shapes and sizes these days — from the size of a cell phone to standard-sized modules for residential, commercial, and industrial use.

Standard residential-use panels are measured in direct-current (DC) capacity. The average solar panel used these days is a 250-watt panel. We use a variety of different panel producers, and due to improvements in the manufacturing process the production standards are very high across the board.

Four of these panels are equal to 1 kilowatt (kW) of DC capacity. (250 watts x 4 = 1000W, or 1kW.)

In terms of energy production, it depends on your specific design factors. Your micro-climate, the latitude of your town, your roof’s orientation and slope, and most importantly your sun access (or how shaded your roof is), all determine how much energy your solar panels will produce.

The production of the system will vary throughout the year, with longer days in the summer producing the most power. The commonly accepted way to measure a panel’s productivity is to take a one-year snapshot of its production. An average system will produce between 1000 and 1500 kWh per year for each kW of solar.

So again, four 250-watt panels (1kW) = 1000-1500 kWh/year.

For one 250-watt panel, you can expect about 250-375 kWh/year.

Under extreme circumstances production goes outside of this range.

Question: What type of roof is best for solar?

Any open, sunny, southern-facing roof!

In reality we can install on a variety of roof types. The most common installations are on composition shingle, flat tile, concrete s-tile or round tile, standing seam metal, and rolled roofing. These are the most common roofing types, and are the best for home solar installations.

Less common, but still doable, installations occur on rubberized roofing, foam roofing, membrane roofing, corrugated metal roofing, clay tile, and ground mounts.

The only kind of roof we will not install on is wood shake roofing.

Question: Should I reroof before I go solar?

Let’s say you went solar today and then a few years later want to re-roof. It’s not that pricey to pop the panels off, re-roof, and then put them back on. And usually, the amount of money you’ll save on your energy bill over those few years more than outweighs the cost of removing the panels briefly to re-roof — so by all means go solar now!

If you were already planning to redo your roof this year or next, go ahead and coordinate with a roofer and do both at the same time — it’s a commonplace occurrence for solar installers to coordinate with roofers like this). If your roof has a few years’ or more worth of life in it, just pull the trigger on solar and worry about the roof when the time comes.

George Shafer, our Lead Solar Designer, has been working with PURE Energies for the last two years and enjoys working to change the way that people think about energy. In his free time you can find him in the waters around San Francisco, surfing, swimming, and freediving.

Solar roofs photo CC-licensed by Kevin Baird on Flickr.

Infographic: The Top Solar Countries in the World — and How they Got There

Mon, 08/11/2014 - 2:03pm

As a companion piece to Garrett Hering’s exploration of the countries that are leading the solar revolution, we created three interactive graphics to help explain not just which countries can boast the most solar capacity, but also to show how they achieved their successes.

Through three graphics, we explore the solar boom. First, let’s look at the overall rise of solar around the world. By clicking and dragging the slider below, you can see how solar has grown between 2004 and 2014 (although the 2014 data are an estimate projected at the end of 2013):

Next, let’s look at the per-capital solar capacity of 10 of the world’s solar leaders:

Finally, and perhaps most importantly, this graphic shows the policy tools that each of the 15 top solar countries have used to grow their solar capacity. Click on the down-arrow next to the country name to see the full list of countries and their policy practices; you can also click on the legend at the bottom of the graphic to highlight all the countries that use net metering, feed-in tariffs, carbon taxes, and others to encourage solar growth.

How the World’s Top Solar Countries Grew Their Markets

Mon, 08/11/2014 - 12:00pm

Solar electricity should reach 1 percent of global electricity demand for the first time ever in 2014, forecasts a new report by the International Energy Agency’s Photovoltaic Power System Programme (IEA PVPS).

This major milestone — though it sounds like a small percentage, it is a big deal for the solar industry — coincides with major changes in solar markets worldwide. Notable among them are a clear shift in demand from West to East in response to reduced government support across Europe and increased incentives in Asia, growing threats to distributed solar power on homes and commercial rooftops in the U.S. and solar electricity prices at or below parity with retail and wholesale grid prices in a number of markets.

The report, which includes preliminary data culled by experts and market participants in IEA and non-IEA countries, estimates that approximately 136 gigawatts (GW) of photovoltaic generating capacity was installed around the world entering 2014 — with the capability of generating an estimated 160 terawatt-hours of electricity — or about 0.85 percent of global electricity demand, according to IEA.

How did we get here? Countries have applied a number of policy and market-based strategies to encourage solar growth over the past decade, including tax credits, rebates and climate change levy exemptions — but far and away the most common are net metering and feed-in tariffs, two incentives that pay system owners for solar electricity sent to the grid.

To accompany the flood of data provided by the PVPS report and other sources, we’ve created an infographic that lists the world’s top solar countries, and also shows which tools they’ve used to reach these heights.

Praise for the 1-plus Percent Club

Although the global solar market is about to hit the record 1 percent mark this year, more than a dozen countries have surpassed that threshold already, according to IEA. A trio of nations – Italy, Germany and Greece – each rely on PV to supply more than 5 percent of their electricity today. Italy leads the way at an estimated 7.8 percent, followed by Germany at 6.2 percent and Greece at 5.8 percent. Bulgaria, Belgium, Czech Republic and Spain are between 3 and 4 percent.

In Europe as a whole, where premium payments for solar electricity fed into the grid (feed-in tariffs) have fueled a boom in PV rooftops and power plants over the past decade, approximately 3 percent of total electricity now comes from photovoltaic systems. At peak demand, Europe’s PV systems even cover up to 6 percent of the continent’s electricity consumption.

The only members of the 1-percent club outside of Europe are Australia, Israel and Japan, whose primarily residential and commercial rooftop markets have been supported by a combination of performance-based feed-in tariffs and net metering payments, and rebates.

Solar Eclipse in Europe

In terms of total installed capacity, Germany still leads by a wide margin with 35.5 GW of PV on the grid at the end of 2013 (see graphic below). Based on installed capacity per capita, Germany also remains way out front with 433.5 watts per person.

Interactive graphic: Top 15 Countries’ Total Installed PV Capacity

But after three consecutive years of adding around 7.5 GW, Germany’s PV market tumbled in 2013 to just 3.3 GW.

“This happened in a context of reduced feed-in tariffs, more constraining regulations for utility-scale PV and the political will to reduce the cost of renewables for electricity consumers,” noted the IEA PVPS report.

IHS predicts that the German market could fall again this year, installing less than 3 GW.

More intense has been the decline of the Italian PV market. After leading the world with 9.3 GW installed in 2011, Italy’s annually installed PV generating capacity dropped to 3.6 GW in 2012 and just 1.5 GW in 2013.

“A financial cap has now been set by the Italian authorities to limit the cost borne by electricity consumers,” explained the IEA PVPS report, adding, “Feed-in tariffs are not granted anymore for new PV installations but a self-consumption scheme and additional tax rebates are now in place.”

Due to its past primacy, however, Italy still is the world’s third-largest producer of PV power, with a total of 17.6 GW online entering this year. On a per-capita basis, Italy ranks No. 2 globally with 288.9 watts per person.

Interactive graphic: Top 10 Countries’ PV Capacity per Person

Italy’s annual PV demand could fall to under 1 GW this year.

Despite a rise in installations in emerging European solar markets like the U.K., Greece and Romania – each of which installed more than 1 GW last year – Europe as a whole declined in 2013 to just over 10 GW. That compares to 17.6 GW of PV installed in 2012 and 22.4 GW in 2011, according to IEA data.

This year, IHS anticipates another year of decline in Europe to just 9.7 GW.

Interactive Graphic: Global Installed PV Capacity, 2004 – 2014

Solar rising in the East

Meanwhile, China is on pace to continue its ambitious ascent. For the first time in 2013, China not only installed more solar power than Germany; the People’s Republic outshined all of Europe by installing 11.3 GW of PV – more than triple the year before – thanks to a potent combination of direct capital investments and feed-in tariffs.

That made China the largest PV market in the world in 2013. Based on a cumulative installed capacity of 18.3 GW, however, China still trails Germany overall.

IHS predicts that China will add another 13 GW this year, including 8 GW at ground-mounted power plants and nearly 5 GW on rooftops.

In a bit of a Fukushima effect, Japan was the No. 2 market for PV in 2013 with nearly 7 GW installed, according to the IEA PVPS report. That was up from just 1.7 GW of PV installed in 2012 and is the result of a new feed-in tariff program launched in mid-2012 in the wake of the catastrophic earthquake and tsunami that — at least temporarily — completely eliminated nuclear power in Japan.

With 13.6 GW of PV on the grid to start 2014 — mostly residential and commercial rooftop systems — Japan currently ranks fourth in the world.

Ash Sharma, senior director of solar research at IHS, expects Japan’s residential market to decline this year.

“Although the reduction in Japan’s feed-in-tariff conformed precisely to IHS expectations, other factors will cause the residential market to decline. These factors include the increase in sales tax on domestic PV systems, the expiration of the additional up-front subsidy and the slowdown in new housing construction,” according to Sharma.

The analyst, however, expects Japan’s commercial and power plant installations to fuel 45 percent growth in 2014 to around 9 GW.

Solar in the New World

The United States, the largest solar market in the Americas, installed 4.75 GW of PV in 2013 compared to 3.37 GW in 2012 — with much of the growth coming from ground-mounted power plants that qualify for a 30 percent investment tax credit.

Combined with lower technology costs, this tax credit has helped to push prices for utility-scale PV into the range of just 5 to 7 cents per kilowatt-hour. Such prices match or beat new sources of fossil fuel generation in many regions of the country and have garnered considerable attention from utilities.

Homeowners and business owners are also taking advantage of lower PV prices in the U.S., leveraging both tax credits and net metering. However, the latter policy has come under attack by utilities in key states such as Arizona, California and Colorado. The residential market in the U.S. nevertheless grew about 60 percent last year, adding nearly 800 megawatts (MW).

With a total of about 12 GW installed at the end of last year, the U.S. ranks at No. 5 in the world in terms of cumulative PV capacity, according to IEA. IHS sees the U.S. market as a whole adding another 6.4 GW this year.

Canada, the second largest PV market in the Americas, which is driven primarily by feed-in tariffs in the province of Ontario, added about 444 MW last year — pushing Canada past 1 GW of total installed PV generating capacity.

Latin American countries, on the other hand, “haven’t developed into a significant market yet,” according to the IEA PVPS report,” even though there has been an increase in development activities.

Despite this year’s 1 percent solar milestone, “PV hasn’t yet reached a widespread development,” finds the report. “On the contrary, the development of PV remains driven by a handful of countries,” it added.

IEA’s statistics show that Germany, China, Italy, Japan and the U.S. accounted for more than 70 percent of the world’s total installed PV generating capacity entering 2014.

In other words, a whole world of solar opportunity is still out there.

Top photo, of the Mityaevo Solar Park in Crimea, CC-licensed by ActivSolar on Flickr.