Author Archives: brandonwalton

Solar racking for different types of roofs

If you decide to put solar panels on your roof, racking systems keep them in place. There are a variety of racking and attachment solutions available to match the many different types of roofs. The best racking system for your home depends on how your roof is structured and what type of roofing materials you have. Your installer will recommend the type of racking system most appropriate for your roof.

Eample

A racking system installed on a shingled roof.

Most homes in the United States feature roofs that are pitched or tilted. These roofs are typically covered with shingles of various styles and materials. Roofers lay down these shingles in courses (rows) that overlap across your roof to allow water to shed from them and not get underneath and leak into your home.

Panels can be attached to these roofs using aluminum rails that are attached to the singles with flashings that slide under several courses of shingles. The panels are then clamped to the rails to keep them securely in place. Another design has panels attach directly to the flashings themselves. The modules themselves act together as the support system for each other.

Ballasted solar installation

Example of a ballasted system. Photo credit: Solardock.com.

Flat/low-slope roofs are usually less than five degrees in tilt. The materials used to cover them vary widely from metal, to modified bitumen to sheet-like covering materials. In addition to the racking systems used in pitched roofs, flat roofs also provide the option of ballasted roofs. These systems use non-penetrating hardware that is kept on your roof by weighted blocks.

Slate can be a difficult material on which to installer solar. Many installers do not work on slate roofs for this reason. In areas where slate is more common, you will find installers who will work on slate roofs themselves or in partnership with a roofing company. Older slate in particular may be too brittle to support solar installation work and may require replacement before installation.

Your solar system should last roughly 30 years, so it is important the roof underneath is in good shape. If your roof is more than 10 years old, you should have it evaluated to determine its remaining lifespan. You may want to consider repairs or replacement prior to installing solar. If you have enough area around you home, you may consider opting for a ground mounted system.

Solar monitoring: Watching your system produce

Improvement in solar technology isn’t just about manufacturing more efficient panels. Advancing solar technology also helps your system perform better over its lifetime. One of the ways this happens is through panel monitoring.

Your system will come with a monitoring portal that you can access via the internet. What your monitoring system tells you depends upon your system, specifically your inverter. All inverters generally have online monitoring options that allow for the tracking and monitoring of whole system production and performance. Micro-inverter monitoring systems give the option for panel-level monitoring. This will show data on individual panel performance.

No matter your specific set up, your monitoring portal will show you the amount of energy your system is generating. You can use this information to verify if your system is producing energy in the quantity it should. Your monitor should be set up to email you alerts if it detects something wrong with your system’s performance.

Keep in mind that energy production fluctuates from day to day, month to month, and year to year based on weather conditions and other factors. Despite those fluctuations, you should see a consistent curve of energy production over time.

The National Renewable Energy Laboratory has put together a useful website, PV Watts, that can estimate your system’s performance. It takes into account the local solar resource and weather conditions as well as your panel orientation, amount of shading and system design to calculate the expected output your system should produce, as well as the financial value of the electricity generated.

If you think something is wrong with the way your system is performing, contact your installer.

Photo of house with solar panels on roof

What is an SREC?

Solar Renewable Energy Credits, or SRECs, can be the most confusing part of going solar. Nevertheless, they are vitally important to understand because they will be worth a significant amount of money over the life of your system.

SRECs are credits you earn based upon your system’s production. Your system will produce one SREC every time it produces a megawatt-hour (1,000 kWh) of electricity. You can estimate the number of SRECs your system will produce by multiplying the size of the system by 1.2. So, a 5-kilowatt system will produce approximately six SRECs each year.

SRECs exist because many states require their utilities to produce a certain percentage of their electricity from renewable energy sources. One of the ways utilities can meet these targets is by purchasing your credits.

This system has led to the creation of a market for SRECs. Think of it as you would the market for stocks or bonds. Prices will rise and fall based upon a the supply and demand for the credits. How you decide to sell your SRECs depends on your individual financial needs and risk tolerance.

There are three ways to sell your SRECs:

  • Sell the rights to all of your system’s SRECs upfront for a cash payment.
  • Sell your SRECs via a contract for a set period of time, usually three, five, or ten years.
  • Register your SRECs yourself and trade them on the spot market.

Selling your SRECs upfront or over a contract period of time is likely to provide you with a lower overall return, but it does provide greater financial predictability compared to selling SRECs on the spot market.

If you are considering a solar lease, rather than the purchase of a system, you should inquire as to who controls the SRECs. The solar company will usually keep the system’s SRECs in this type of financial arrangement.

You can learn more about SRECs and the pros and cons of the different ways to sell them here.

Tell me about your solar job, part 1

The solar industry employs workers with a range of skill sets. We thought it would be interesting to hear from them in their own words. Today we spoke with JD Elkurd of Solar Solution, Jeff Nicholson of Sigora Solar, and Ryann Coles of Altenergy Incorporated about their jobs and the solar industry.

How did you get involved in the solar industry?

JD Elkurd: I am extremely passionate about sustainability and green living, I was also seeking a rewarding career to where I would feel I was actually helping changing the world for the better.

People think of solar jobs as just being up on a roof installing panels. What other types of positions or employees do solar companies look for?

Jeff Nicholson: About two-thirds of our employees are installers or field supervisors. It takes a lot of labor to get a PV system installed. However, it takes a lot more than just an installation crew. We employ an accountant, a CAD designer, a permitter, a troubleshooter, a logistics manager, a marketing director, a product development engineer, and even a video engineer.

What skill sets do you see as most important to building a career in the solar industry?

JN: We have employees from all backgrounds. The traits they all share are an enthusiasm for what we’re doing, a dedicated work ethic, and a technically-oriented mindset.

JE: Passion for the environment and renewable energy will always come first. Second I would say is creativity in design. The rest can all be learned.

Can you describe your typical day or week on the job?

Ryann Coles: I wear many hats. I work on proposals and contracts, net metering agreements between clients and the utilities, register SREC applications, work with the USDA and grant applications, marketing, to name a few.

JE: Our construction manager meets our installation crews in the morning between 8am-9am to go over the project at the site. In the office our sales coordinators are identifying possible projects around the city and reaching out to home and business owners, our design consultants are designing systems on prospected sites and drafting up proposals, and our sales guys are going out to meet home owners and business owners to moving forward with solar PV projects.

What is the most rewarding part about your job?

JN: Beyond the beneficial effects of solar energy, installing for our customers gives them a sense of pride and excitement that they pass on to others. Solar is highly contagious.

What was the most surprising thing about your job?

JN: The most surprising thing about my job is the interesting range of questions I get asked about solar. My favorite question from someone at an educational session was: “Are these panels vulture-resistant?… My wife is a wildlife rehabilitator, and through her I’ve had a fair amount of exposure to vultures. I knew enough to be able to reassure him that our solar modules (which can withstand a truck driving on them) were 100% vulture resistant.

Is there anything else you’d like to add?

RC: I love my job!

Kanawha County Solar Co-op selects AAT Solar to serve group

The Kanawha County Solar Co-op has selected AAT Solar to install solar panels for the group. Co-op members selected AAT Solar through a competitive bidding process. The group will hold its final public information session on January 27, 2016 at 6:00 pm at Blessed Sacrament Church (305 E Street, South Charleston, 25303) to educate the community about solar and the co-op process.

The co-op is open to new members until March 14. Kanawha County residents interested in joining the co-op can sign up at the co-op webpage. Joining the co-op is not a commitment to purchase panels. AAT Solar will provide each co-op member with an individualized proposal based on the group rate. By going solar as a group and choosing a single installer, each participant generally saves up to 20% off the cost of their system.

Information session details

January 27
Blessed Sacrament Church
305 E St., South Charleston, WV 25303
6:00 p.m.

Alternating Current, Direct Current, solar, and you

(This post was written by WV SUN Communications Fellow Garance Perret)

Every solar system comes with a device called an inverter. Inverters are a key component of your system. They convert the energy gathered from the sun by the panels to the energy needed to power your house. That is to say, inverters transform direct current (DC) into alternating current (AC). To understand why this change is necessary, let’s look at the difference between DC and AC.

Electrical current is the flow of charged electrons. The difference between alternating and direct current is the direction in which the electrons flow. With direct current, the flow of electrons moves in one direction. With alternating current, the flow of electrons oscillates, creating a wave-like pattern.

Most household appliances and buildings are powered by AC because it is much easier to change the voltage level of AC. Additionally, AC  is better transmitted over long distances. In electricity’s early days, there was fierce competition between engineers as to which was the most efficient.

Thomas Edison was a strong backer of using DC. He even led a campaign in discouraging the use of AC citing safety concerns. AC became dominant at the end of the 19th century when engineers saw its ability to transmit power over longer distances.

Let’s explore how those differences apply to your system. Your system’s electrical output is measured in watts. It is important for you to be clear if that measurement refers to the panels’ AC output or its DC output. A panel’s AC output is different than its DC output: think of it like a currency exchange. One dollar is a different value than one euro.

Although AC won out as the electric current used by your home and appliances, many devices, such as batteries, still use DC. DC is also the form of electricity generated by your solar panels. This is why solar panel manufacturers label the output of their panels in DC.

Panels output measurements come in two ways: Standard Test Conditions (STC) and Performance Test Conditions (PTC). STC refers to a panel’s output under laboratory conditions. This is the most amount of electricity it could possibility produce. PTC measures a panel’s output in real-world conditions. To calculate your panels’ output in AC you multiply the aforementioned PTC measurement by your inverters’ efficiency – usually around 95%. This means the DC measurement will always be a larger value than the one for AC.

So you might wonder, is one measure better than the other? No, but is important when you are comparing quotes, that you are clear on which metric is used. This way you can make an apples to apples comparison.

Solar electric and solar thermal: Using the sun to save money

(This post was written by WV SUN Communications Fellow Garance Perret)

When people talk about ‘going solar’, there are two technologies they generally mean: solar electric and solar water heating. Although they both use the sun’s energy, solar electric systems and solar water heating systems use that energy in different ways.

Solar electric systems use sunlight to generate energy. Light particles hit electrons in the panel, creating an electric current. This current then powers your home and appliances. Solar electric systems vary greatly in size. They can be as small as a handful of panels on a remote hunting cabin, a few dozen panels on your home, or thousands of panels arrayed in the desert.

Solar water heating systems use heat from the sun to raise the temperature of the water you use in your home. This is done either by heating the water directly, or by heating a transfer fluid.

The collectors used in solar thermal systems do not have the complex electronics that solar electric panels have. In solar thermal systems, water passes through the collectors’ tubes where it is heated by the sun’s energy. The water then goes through a heat exchanger for storage and later use. The system is accompanied by a water tank modeled on a standard hot water heater.

As with solar electric panels, solar hot water systems do need occasional maintenance over their lifespan. Your water pump may need replacement once or twice over the roughly 30-year life of the system. You should also have your transfer fluid checked every three to five years.

You can learn more about solar hot water systems here.

Tax credit extension good news for solar community

Last week, President Obama signed the Omnibus Appropriations Act. Included in the legislation was an extension of the federal solar customer tax credit. This credit was set to expire at the end of next year. The credit allows solar customers to deduct 30% of the cost of their system off their taxes. The customer tax credit puts solar on a level playing field with other electricity sources.

The new legislation extends this tax credit at 30% through 2019. The credit then lowers to 26% in 2020 and 22% in 2021. It expires in 2022. Solar supporters fought hard to extend this important solar policy, as its expiration would have harmed everyone’s ability to access clean, locally-produced energy.

This smart policy has helped the average price of a solar panel decline by more than 60 percent since the beginning of 2011. There are now 174,000 Americans working in the solar industry. The tax credit’s extension will make it possible for more people to go solar.

Studies find solar increases home value

(This post was written by WV SUN Communications Fellow Garance Perret)

The financial benefits of solar aren’t limited to lower electric bills. Solar can significantly increase the value of your home. Numerous studies have found that solar can add a premium to your home’s resale price. Solar has become the new granite countertops. As solar has become more popular, a number of organizations have tried to assess the value these systems provide.

The National Renewable Energy Laboratory (NREL) was one of the first organizations to attempt answering the question in 2006. NREL’s research examined a number of factors that impact solar’s value. These include the initial value of your home, its location, and the size of the solar installation. NREL found that a home with solar sells 20% faster than a home without solar, and for a price about 17% higher. For each $1 solar saved on your energy bill, approximately $20 was added to your home value.

In 2011, the National Bureau of Economic Research posted an analysis of the price premium on solar homes. The study found that a $22,500 solar panel system would increase your home’s value by 3.6% .

Most recently, the Department of Energy’s Lawrence Berkeley Laboratory studied the impact of solar on homes in California. This study examined data from 1999-2013 and found that solar increased the value of a home by nearly $6,000 per each kilowatt of solar installed.

These studies show how solar can be a smart investment beyond just energy prices. As more and more homeowners add solar we’ll have further proof that energy independence as a boost to home value.

A brief history of solar energy

(This post was written by WV SUN Communications Fellow Garance Perret)

The use of energy from the sun goes back a long way. Before we discovered that the sun’s light could be collected to produce electricity, people took advantage of it in other ways. We used passive design to take advantage of the climate to maintain a comfortable temperature in our building. Passive design reduces or eliminates the need for auxiliary heating or cooling and has been used by civilizations for millennia. Ancient Greeks and Egyptians, as well as Native Americans, built homes and cities to have the most energy efficient sun exposure. They faced their buildings south, like we do with our solar panels.

Greek and Roman architecture developed with solar energy in mind. Porticos – series of thick and evenly spaced pillars – were built in order to let sunlight filter through. This allowed for the right amount of light and heat to come through.

In Ancient Egypt, black tile-lined pools of water collected solar energy throughout the day. At night, water would be used to keep palaces warm through the heated pipes.

It wasn’t until the 19th century that we began turning the sun’s light into electrical energy. In 1839, French Physicist Alexandre Edmond Becquerel discovered the photovoltaic (PV) effect. The PV effect is the creation of electric charge as the result of exposure to light through the stimulation of electrons in metals such as selenium or platinum as conductors.

Aleksandr Stoletov developed the first solar cell based on the photoelectric effect in the late 19th century. The industry didn’t begin to grow, however, until the development of a silicon-based solar cell by Bell Labs in the 1950s. The development of individual solar cells led to the manufacture of panels, which are a collection of solar cells. Solar panels are the optimal surfaces to capture the most light.

Throughout the 1950s, the efficiency of solar cells kept on increasing, from 8% in 1957 to 14% in 1960. The space race created a need for sustainable energy sources. It steered investments and development in the solar industry. In the 1960s, the first telecommunication satellite TelStar 1 launched by Bell Labs feature the most cutting edge solar cells.

Despite the great advances made in solar technology, it was not commercially viable yet due to its high price. As hard as it may be to believe, the initial push to lower the cost of solar came from oil companies. They recognized the future financial difficulty of sustaining energy production with oil. So, they started to invest in solar. Backed by Exxon, Dr. Elliott Berman designed a much less expensive solar cell. He brought the cost per watt down by 80%.

Since 2008, solar power has become increasingly popular as a renewable form of energy, as its price became affordable to a much wider market. Research and investment in solar technology continues at an energetic pace, with no shortage of engineers and innovators. Solar manufacturers continue to pursue technological improvements to make solar panels more efficient and less expensive.