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The Layman’s Guide To The Value Of PV Solar

by Guest Author March 21, 2016

written by Guest Author

The PV solar industry is experiencing explosive growth and many homeowners and business owners are being approached by solar companies to buy or lease a solar system. The purpose of this solar guide is to provide consumers with real numbers and objective information so they will be educated on what to expect from installing solar. This guide will explain common terms used in the industry and during a sales presentation.

Solar salespeople commonly present potential customers with the estimated production in kWh (Killowatt Hours) for the solar PV (Photovoltaic) system, and the value of that production by comparing it to the current & projected utility rate. From this analysis a customer’s estimated savings is presented.

Production in kWhs

The most important factor for calculating customer savings is estimating the production in kWh. The production of a solar system is dependent on many factors. In order to simplify things, we will narrow it down to the main variables:

● Size of the system. Solar PV systems are rated by watts. A 10 kW (Killowatt) system will produce 10,000 watts of electricity per hour in rated conditions. These conditions are defined as Standard Test Conditions (STC). Essentially these are laboratory conditions that do not normally reflect operating conditions. The size of the system is the most easily identifiable, and objective, attribute of the solar system’s capability and potential.
● The amount of sunlight at the site’s location. Sunlight varies with location and season. Arizona has the most sunlight in the U.S., while Alaska has the least.
● Shading can have a significant impact on solar production. Shading can come from a nearby roof or a dormer on the same roof. Most often they come from trees. Different seasons and times of the day can complicate matters, since the Sun moving across the sky can cause partial shading. In addition, the Sun is higher in the sky in the Summer and lower in the sky in the Winter. Solar installers have tools to calculate all the shading variables.
● Direction of the roof. The Sun is in the southern part of the sky and it travels East to West. As such, South, SouthEast, and SouthWest roofs generally receive the Sun’s exposure. A southern roof orientation is ideal, receiving the maximum exposure of the sun throughout the day and year.
● Tilt of the roof and/or panels. Being that the Sun shines at a certain place in the sky, different angles will affect how the sunlight hits the panels. The rays hitting the panels at the most direct angle will create the most production. On average, a 30 degree tilt (7/12 pitch) is optimal.

By definition, any deviation from ideal conditions lowers production a certain amount. NREL (National Renewable Energy Laboratory) is a government entity that tracks, among other things, sunlight at different locations throughout the World. They are able to project the amount of sunlight in the future based on the previous 30 years of data. NREL runs a website called PV Watts (http://pvwatts.nrel.gov/) which is able to calculate the projected production from a solar PV system.

This NREL calculator takes into account all of the above mentioned attributes, plus more. It then is able to project how much production a given system will produce by the year, and even per month. An installer who is putting together the projection has the ability to modify many factors to get as accurate a picture as possible.

Example:
A 10kW system at a 30 degree tilt angle facing 180 degrees azimuth with minimal shading in New Jersey will be estimated to produce 13,500 kWh per year.

Value of Production

Calculating the value of the solar system’s production is much simpler. One would first need to figure out what they are paying per kWh. Electric companies have different ways to present their bills. Since solar generates and delivers the electricity to the home or business, it lowers the Generation and Delivery portion of a bill. Some utilities charge for different times of day but we will try to simplify things:

● Add up the billed amount of all the line items that have kWh (NOT the KW, which is the calculation of the maximum amount of electricity that was needed at any given point).
● Divide it by the highest kWh amount specified (which is the total usage for that month) That number is the approximate electric rate. There are seasonal changes to the rate but it can be averaged out. The value of the production is the utility rate multiplied by the estimated annual solar production.

Example:
If the utility company is charging $0.16/kWh and the estimate annual production of the solar PV system is 13,500kWh a year then the value of what the solar is producing is $2,160/Year (.16×13,500).

Utility & Solar Rate Comparison

This is very straightforward. We already calculated the value of the production, as per the Utility Rate (in our example $2,160/year). Most solar proposals include a projection that the utility rate will go up at a certain percentage every year. They then compare that to the Lease/PPA/”Free Solar” rate, on an annual basis, to show how the savings increases over time.

Example:
In our example we won’t calculate the projected Utility Rate increases. If the Lease rate is $0.09/kWh then the annual savings will be $945 ($2,160($0.09×13,500)).

A few things to be aware of:
● The percentage that the solar company assumes regarding the projected utility rate increase can affect how much they portray the total savings to be. If one company states a 2% escalation and another says 5%, the one who said 5% will show a much larger amount of savings over the course of the life of the system. They don’t have control over that number, they are just projecting the future cost of utility energy differently.
● If one purchased the solar system they can calculate the IRR (Internal Rate of Return) or figure out when the Break Even Point will be and then have free electricity after that. Purchasing the system up front gives an immediate feeling of savings by avoiding a bill. Although the majority of residential systems installed today are through some sort of Lease or PPA agreement, there are many people who choose to purchase a system up front.
● Certain states provide solar system owners additional sources of revenue through REC or SREC (Solar Renewable Energy Certificates) programs. Someone who purchased a system, or receives the SRECs through their lease, earns a credit for each 1,000kWhs produced by the system. They are then able to monetize those credits through various mechanisms that the states setup. This can have a significant positive effect on owner’s cash flow. Example: 13,500 will produce 13.5 SRECs (assuming the half a credit will be split over two years). If these SRECs are selling for $100 then the total revenue from the SRECs will be $1,350 for the year. In many States these SRECs can fluctuate in price, contracts for a multiyear setprice are sometimes available.
● A purchase can also benefit from tax incentives, state rebates and other benefits that are
dependent on the location.

As incentives are often changing, it’s important to be aware of the current financial offerings that are available. Solar lease prices also can adjust as the incentives, and competition, change. Solar has tremendous value and in order to take full advantage of all that solar has to offer one should be knowledgeable to make the best educated decision.

By Cy Yablonsky, Vice President PowerLutions Solar

March 21, 2016 1 comment

PV Solar $Solar Projects

410 GWh Solar Electricity Purchases By Endesa In Spain

by Guest Author March 21, 2016

written by Guest Author

Originally published on Sustainnovate.

The Spanish utility company Endesa purchased 410 gigawatt-hours (GWh) of solar electricity during a recent solar energy auction for Portugal and Spain, according to recent reports. The solar auction in question ended with a price of €39.6/MWh/megawatt-hour ($43.82).

The aforementioned 410 GWh of solar electricity equates to roughly 681 megawatts (MW) of nameplate capacity.

As of the middle of last year, the Spanish utility company has been “encouraging” that quarterly solar energy auctions be held by the independent Iberian Energy Derivatives Exchange (OMIP), for the Iberian peninsula. The quarterly auctions relate to roughly 500 GWh of generation, varying somewhat depending on the level of production at the various times of year.

An Endesa rep commented on the successful auction, stating that it had reaffirmed the “positive market acceptance” of the approach.

A separate release from the company stated: “Until the solar auctions began, the wholesale forward market had not offered the financial risk management tools in a transparent, reliable and competitive environment, required to meet the specific profile of solar production.”

“This auction has also enabled the creation of a specific index for solar products (SPEL Solar), the first in Europe which also serves as a reference to analyse the progress and behaviour of this technology in the financial markets.”

The next quarterly Iberian solar auction is slated for June 2016.

Notably, Endesa is a part of Enel Group, along with Enel Green Power, a 2015 Zayed Future Energy Prize finalist and one of the largest renewable energy project developers and operators in the world.

March 21, 2016 0 comment

Rooftop Solar

Home Solar Is Your Local Clean Power Plant

by Guest Author January 8, 2016

written by Guest Author

Originally published on Home Solar PV.
By Jeff McIntire-Strasburg

You can be forgiven for not wanting to live next door to a traditional power plant. They’re big, noisy, and smelly, and even with the most modern of pollution controls, you probably still don’t want your family breathing whatever’s coming out of them. When it comes to coal or natural gas-powered electricity generation, it easy to understand a “not in my backyard” (NIMBY) position.

home-with-solar-panels But what about the neighbor putting solar panels on his roof next door? Isn’t that essentially a power plant? Yes, it is… but the very best kind: no noise, no air pollution, and no carbon emissions. And while some neighborhoods do take a NIMBY position on solar panels, or insist that you keep your solar array out of sight, there’s no real reason to believe that this kind of power plant will negatively impact your quality of life, or your property value.

Home Solar Arrays: Clean, Quiet Power Plants

Solar panel arrays, the most obvious parts of home solar power systems, collect energy from sunlight through the photovoltaic effect: photons in sunlight strike electrons in a silicon panel that’s been “doped” with phosphorus, and that sub-atomic level movement forms an electrical current. While that’s a very simple description of the chemical activity occurring in a solar panel, it’s enough to show already that this is a much cleaner process: no burning, no emissions, no wastes requiring disposal.

That power does require conversion, though: solar panels produce direct current (DC), and all of our electrically-powered appliances, gadgets, etc., require alternating current (AC). So, that current heads down a wire to an inverter, which converts DC into AC, which can then be used in our homes.

But what if we don’t need that power? This has been the point at which many renewable energy advocates get stumped: what do we do with power that’s been generated, but isn’t currently needed? For most of us considering a home solar power system, that’s a pretty easy question: the power will go onto the electrical grid. Assuming you live in a state with net metering – a requirement that utilities buy power that consumers produce through renewable energy systems – your electric meter will actually run backwards if you’re producing more power than you’re consuming.

If you’re not connected to the electrical grid, then you’ll need to install a bank of batteries to store the energy you produce. You can do this with a grid-connected system, also, to avoid power outages that still come with grid connections; these complex systems, however, get really expensive.

Regardless of your grid connection, you’re now ready to plug in and enjoy that electricity produced by the sun.

Can My Solar Power Plant Take Care of All of My Electricity Needs?

That depends on a number of factors. First, how efficiently does your family use electricity? Do you have updated, very efficient heating and air conditioning (which are the biggest energy users in most homes)? If you have an electric water heater, is it running at maximum efficiency? Are your refrigerator, washer and dryer, dishwasher, and stove/oven all high-efficiency models? Are your insulation levels at recommended levels, and are your windows and doors properly weatherized? If you’re installing a grid-tied solar system, it’s good to take a page from the off-grid crowd and make sure that you’re making the most efficient use practical and possible of the electricity from your solar power system.

Another off-grid practice you may want to emulate: do your most electricity-intensive tasks at times when your photovoltaic system is producing the most energy. Generally, that means when the sun is high in the sky, and the sun’s rays are hitting your system’s panels at a right angle. Depending on your location, and the time of year, the amount of peak time that you’ll have on any given day will vary.

Solar Power Systems are Clean and Green: No Noise, Smell, or Pollution

Regardless of what percentage of power your solar system provides for your home, it will do it in a manner that’s the total opposite of a coal-burning or gas-burning power plant: no noise, no smell, no pollution. Your neighbors shouldn’t even notice it.

Traditional power plants represent the largest source of carbon dioxide emissions, the main greenhouse gas that contributes to global climate change. Globally, power plants create three-quarters of our CO2 emissions; in the United States, the account for 82%. The Obama administration has instituted the Clean Power Plan to cut the CO2 emissions from power plants run on fossil fuels, and to speed our momentum towards a clean energy economy. That solar power plant on your roof, however, creates no emissions: once it offsets the energy needed to build and install it, your solar system will reduce your family’s climate impact with every use of electricity.

If your power comes from a nuclear power plant, you may think you’re covered on the environmental front: nuclear reactors also don’t emit greenhouse gases in the production of electricity. Nuclear plants have other downsides, though. Like coal and gas-burning plants, they’re still huge and noisy. They produce radioactive wastes that will last for thousands of years. They take many years to build, and are very expensive. Finally, while nuclear reactors are generally very safe, they do present a very small risk of catastrophic, long-term destruction. As with other traditional power plants, a NIMBY response to nuclear reactors makes some sense.

Before solar power became readily available and affordable, only the most die-hard off-gridders considered installing their own power plant. As the prices have dropped on home solar arrays, and as governments and utilities have offered various financial incentives, the notion of generating your own electricity become much more mainstream. And the sun is the source of all energy on the Earth: coal, oil, and natural gas are essentially solar power with lots of other less desirable components. Why not go directly to the source?

If you’re thinking about investing in your own home solar power plant, take a look at the tools we’ve created to give you an idea about the costs involved. If you already generate part or all of your own electricity with solar panels, share your experience with us in the comments…

Photo credit: CreativeNature R.Zwerver via Shutterstock, Marina Lohrbach via Shutterstock

Reprinted with permission.

January 8, 2016 0 comment

Rooftop Solar

Free Home Solar Installation

by Guest Author January 8, 2016

written by Guest Author

Originally published on Home Solar PV.
By Jeff McIntire-Strasburg

Seen an advertisement recently promoting “free solar installation” or “free solar panels” for your home? Figured it was probably some kind of shady deal with lots of catches involved? Perhaps, and you’re smart to investigate further. But don’t necessarily write those claims off, either: the offer of “free solar installation” may well point to a legitimate transaction that gets solar panels on your roof, and solar-generated electricity to your appliances and gadgets. If you want to explore such an offer further, ask the salesperson, “Are you selling a power purchase agreement (or PPA)?”

What is a Power Purchase Agreement?

solar-panel-installation-on-new-home In contrast to purchasing solar panels outright, a PPA is a long-term (generally 20-25 year) contract to buy the electricity generated from a solar array. You don’t have to buy any equipment; you just have to agree to purchase the electricity produced by solar panels placed on your roof or other location. The panels themselves are “free” because you don’t own them: the company with which you have the agreement owns the solar array. All of the tasks that go with such ownership fall on them: maintenance, repair, cleaning off snow, etc.

The term “solar leasing” is often used with these arrangements, and that may help you wrap your head around the concept. As with other leasing or renting arrangements – a car, a DVD, a power tool – you don’t necessarily want to own the item in question – you just want the use, or benefits, provided by it. Power purchase agreements give you access to clean electricity without the responsibilities that come with solar panel ownership.

So, what’s the catch? There really isn’t one: you continue to use electricity as you would, but, when conditions are right, that power will be coming from the solar panels rather than your electric company. You’ll stay connected to the electrical grid, so you’ll always have power regardless of whether the sun’s shining or not.

The main benefit of a PPA should be obvious: no large upfront payments to get solar power. Given that installed solar power systems can run from $20-30,000, that’s a significant upside for most of us. You’ll also save money over the long-term vs. traditional electricity: the rates you pay for the electricity generated from the solar system will usually be lower than power company rates, and they won’t rise as much over the course of the contract. Generally, you can count on paying 10-15% less for the power that comes from the solar panels. A final benefit: you won’t have to worry about the extra responsibilities that come with solar panel ownership. The company that owns those panels only makes money if they’re working properly, so it’s to their benefit to make sure that array is stays well-maintained and free of debris, snow, and other things that might interrupt the flow of power.

Of course, there are downsides, too. Giving up the responsibility of owning your own solar array means giving up the financial benefits that go with it, also. When the system on your home or property, for instance, sends power back to the electrical grid, the company that owns it will receive that payment. It will also be able to claim any tax incentives, utility rebates, and other financial incentives.

So, Which is Better: a PPA, or Purchasing a Solar Array?

There’s no settled answer to that question: it definitely depends on the amount of power you can expect to generate from your solar array, the financial incentives available, and the financing options. Your location makes a huge difference: not only do some areas have better solar resources, but some states (like California and New Jersey) have invested more in financial incentives for their citizens and businesses.

You’ll definitely want to run the numbers for all of your options. Make sure you explore all of your options, including the following:

Tax credits and deductions: If you buy a solar power system for your house in the United States before the end of 2016, you can take advantage of a 30% federal tax credit. Depending on your location, other tax incentives may be available: a review of information at the Database of State Incentives for Renewables & Efficiency (DSIRE) will give you information on state government and local utility financial incentives.

Financing programs: While you could certainly use home equity or other conventional financing to pay for a solar system, numerous states and banks offer loan program tailored specifically for renewable energy. Many of these programs require no down payment, effectively creating another option for “free solar installation”… but you own the panels.

In a number of locations, Property-Assessed Clean Energy (PACE) programs are available. With these programs, loans are made from state or local governments from bond funds; borrowers’ payments are incorporated into their property tax bills. These programs can also fund energy efficiency upgrades you need to make to your home or business to take the greatest advantage of your solar system.

Net metering: Can you sell the excess electricity you generate back to your local power company at retail rates? Known as “net metering,” this option is available in many US states, and some utilities offer it voluntarily where it’s not required. According to the Solar Energy Industries Association, 20-40% of a solar array’s output may end up going back to the grid, providing a significant cut to your electricity bill.

Want to get a better sense of what’s available in your state? The National Conference of State Legislatures breaks net metering program down for you.

Home value: Despite what some neighborhood homeowner associations seem to think, solar panels can add value to your home: a 2011 study that focused on California homes found that a seller could count on recouping the cost of his/her solar array. A power-purchase agreement, on the other hand, could end up costing you money when you go to sell because the panels aren’t part of the sale; the buyers may have to qualify for a contract with the PPA company, or you may have to pay a penalty to break your own contract.

Feeling a bit overwhelmed by all of the options here? No problem – the solar calculator at Cost of Solar can run the numbers for you, and show you what options will serve your needs best.

Photo credit: Udo Kroener via Shutterstock

Reprinted with permission.

January 8, 2016 0 comment

Rooftop Solar

Financing Home Solar

by Guest Author January 8, 2016

written by Guest Author

Originally published on Home Solar PV.
By Jeff McIntire-Strasburg

Even though the price of solar panels has dropped over the past few years, a solar energy system for your home will still cost $20,000 – 30,000. Most of us don’t have that kind of money just sitting around: if we do have those kind of assets, they’re tied up in home equity, our retirement savings, or other investments. And while you can leverage that wealth through a conventional loan, if you’re serious about solar power for your home, you’ll want to check out the range of financing options available. As demand for these systems has grown, financial institutions, state and local governments, utilities, and manufacturers have all created alternatives for solar energy financing.

Your First Consideration: Do You Want to Own the Solar Array on Your Roof?

family-with-solar-panels If you’re relatively new to home solar power, that question might have you scratching your head. What other options are there? A variety of third-party solar financing options, however, give you the benefits of solar-generated electricity without the responsibilities of owning the system that generates that power.

The two main alternatives here: the solar lease, and the power purchase agreement (or PPA). The first involves leasing the system itself: as you would with any other product your might rent or lease, you make regular payments to use the system that’s owned by someone else. Various options might include no money down, or lease to own.

As with a lease, a solar system used in a PPA is owned by the company offering its use, but instead of leasing the system itself, a customer pays for the power the system generates. The advantage here is that the cost of power from such an arrangement is generally cheaper than local utility power; the price also won’t rise as significantly (and you’ll know up front when cost increases are set to occur). A customer can expect to save 10-15% on the electricity s/he purchases from the solar array.

While third-party systems are popular, and represent the majority of home solar power systems in a number of states, they do come with downsides. The owner of the array gets to take advantage of all financial incentives offered by state and local governments, and power utilities. They can also create headaches if you want to sell your home, and possibly even hurt your home’s value. If you’re planning to stay put, and just want solar power with minimal investment, though, these arrangements are worth exploring.

Options Available for Future Solar Power System Owners

Owning a solar system come with its own benefits and drawbacks: you get the financial incentives available to you, but you’re also responsible for maintaining and repairing your panel array. If you’ve figure out that you’d rather own your solar energy system, make sure you explore all of the financing options available. In addition to conventional loans secured by home equity or other assets, you may have options available specifically for renewable energy systems.

Solar loans: Some banks and finance companies offer unsecured (no collateral) loans for solar systems, or loans that use the system itself as collateral. Because such loans are riskier for the lender, you’ll pay more in interest than you would with a home equity or other secured loan. Depending on the size of your solar system, and the percentage of your home’s power need it covers, you may end up cutting your electricity spending immediately.

You may also want to check for loans from banks or governments that tie payments to the expected energy savings produced by the system you plan to install.

If you’re interested in this kind of financing, you may want to explore options from Admiral’s Bank, Dividend Solar, and Mosaic.

Property Assessed Clean Energy (PACE): A newer option available to residential and commercial property owners in many states, Property Assessed Clean Energy (or PACE) programs offer a number of benefits for going solar (or, often, for improving your home’s energy efficiency). PACE loans come through state or local governments, and are tied to a property (rather than the owner). As such, they don’t create hassles if you choose to sell your home, because the loan doesn’t have to be paid off at the time of the sale. Payments are added to the homeowner’s property tax bill, and this can lead to lower interest rates because of the high security tied to such an arrangement. In some cases, repayments for PACE loans may be deductible from income taxes (also because they’re tied to property taxes).

Twenty-three states and the District of Columbia have passed legislation enabling PACE programs, but not all of those states have an active program running at this point. PACENation has a current list of programs and their status.

Other Financial Benefits of Ownership

If you choose the ownership option, various incentives offered by your state and local governments and utility providers may bring the price of your solar energy system down further. Among the types of incentives available:

Net Metering: More than likely, your home is already connected to the electrical grid, and you plan to keep that connection after installing a solar system. Net metering requires that utilities “buy back” any excess generation from your home-based “power plant” by crediting your account at the retail rate. This means that any power you use that doesn’t come from your solar panels will be partially, or maybe even totally, offset by electricity you send to the power grid.

Tax credits and deductions: The US federal tax credit for solar systems provides a significant incentive for going solar: homeowners can claim a tax credit of up to 30% of qualified expenses tied to their solar purchase (or a few other renewable energy systems) – currently this incentive is set to expire at the end of 2016. States and municipalities may also offer such credits and deductions.

Rebates: Electrical utilities may offer cash rebates on your solar system, as well as on energy efficiency measures you take in anticipation of installing solar.

Grants: For lower-income people interested in the environmental and economic savings that come from solar power, grants may be available to cover some of your costs.

Want to learn more about the financial incentives available to you. Spend some time on the Database of State Incentives for Renewable Energy (DSIRE). This very thorough database shows you everything that available to you by your location. A reputable solar installer should also have some insight into the incentives for which you might qualify.

Want to learn more about what kind of financing options might work best for you. Head over to Cost of Solar to generate a free report on the solar potential for your home.

Photo credit: Andrey Popov via Shutterstock

Reprinted with permission.

January 8, 2016 0 comment

How To Save Money On Your Solar Panel Installation

by Guest Author January 2, 2016

written by Guest Author

Installing solar panels on your home or business can be an effective way to reduce your fossil-fuel energy footprint, while also reducing your electric bills for decades to come. The investment in clean electricity through solar energy can offer an ROI as good as, or better than, many other conventional investments, but it does require a commitment, as a home solar array isn’t exactly a plug-and-play project, but is meant to be installed semi-permanently so as to offer years of maintenance-free service.

2903370723_09ee528f91_z To get the most savings on your home solar panel installation, there are a few angles to approaching the project’s cost savings, with some of them leveraging your time or your money or your labor, and others leveraging the competitive nature of today’s home solar companies.

Save some now or save more later: When considering solar panels, it’s important to remember that they are built to last for decades, and that they can have a bit of a decline in efficiency as they get old (although not a significant enough one to make that a serious issue in most cases). However, there are also are a great number of different makes and models of solar panels on the market, so it’s possible to buy really cheap solar panels that offer an upfront savings, or to buy higher quality panels that cost more initially, but which will pay off in greater efficiency and longer life over the long run.

Save on finance charges: Paying cash for big-ticket items can almost always deliver a significant savings, when compared to the interest and fees owed due to borrowing the money, so if you have the means to cover the purchase of the solar installation up front, it can pay to do so.

Save through solar incentives: Many places have solar incentives, and whether they are national or local or regional rebates or tax credits (or utility-based incentives), it’s time well spent to find out what levels of incentives are available for you in your specific location.

Save by doing your homework: Before you go out and get some solar bids, it’s helpful to understand what the going rates are for solar installations, what the average size and capacity is, what your regular home electricity demand is, what your current cost of electricity is, and other related issues, so you know the right questions to ask of any potential solar installers.

Save by doing an energy audit first: Energy conservation is always cheaper and more effective than producing more energy, even if it’s renewable energy, so before you explore a home solar installation, have an energy audit done first, and then take action to reduce any unnecessary energy demands. When done first, your new solar electric installation will be as effective as possible in reducing your home energy bills, because you’ve cut out your energy waste.

Save by shopping around for bids: When looking into getting a home solar installation, be sure to get a number of different bids and proposals from qualified solar contractors, which will allow you to know that you’re getting the best deal possible before committing to it, and to find the best cheap solar panel installers.

Save by getting the right size of solar array: A solar array that is too small to offset enough of the home’s energy demands isn’t going to save much money, so it’s important that any solar proposals take into account the average baseline energy demand of the house, as well as any peak energy needs, so as to appropriately size the solar array.

Save with a DIY installation: If you’re handy with tools and don’t mind putting in the time and energy to do the work, most of a home solar installation can be done by yourself. A DIY-er can do everything from getting the permit to buying the solar panels, the mounting system, the inverter, and the necessary wiring, to installing the actual racking and panels, and can then have a qualified electrician do the wiring and any additional technical details.

Solar panels can save money for homeowners year after year, and although purchasing a home solar installation can require an investment, it’s possible to save more money on the project with one or more of these approaches.

This article has been sponsored by solarpanels.cheap

Image: Jeremy Levine

January 2, 2016 0 comment

PV Rooftop Solar

The Future Of PV: Consume All You Capture

by Guest Author December 7, 2015

written by Guest Author

By Stu Statman, Vice President of Engineering at Sunverge Energy

Hawaii’s Public Utilities Commission recently approved two new tariffs to cover future rooftop solar installations, including an option that’s gaining favor with consumers: Solar “Self-Supply.” Also known as “PV self-consumption”, it’s an option where a home consumes all the solar energy produced by its PV system, rather than pushing a portion of that power out to the grid.

perfect-pv-consumption For consumers, Solar Self-Supply can keep their energy costs quite low, because the nominal price for a kilowatt of solar energy is zero. That’s especially important in a place like Hawaii, which has some of the highest retail electricity rates in the nation. While PV self-consumption sounds good in theory, it’s a lot harder to achieve perfect PV self-consumption in practice. The hours of the day that produce the greatest amount of solar power also happen to be times when most residential consumers have the least use for it. Another one of the challenges in doing perfect PV self-consumption is having the inverter follow the load exactly. Because of how electricity meters report data (in samples, not continuously), the inverter has to chase the demand, leading to small amounts of power being imported and exported.

The way to solve these problems and rebalance supply and demand is with energy storage, in the form of batteries connected to the PV installation. With the right storage system, consumers can capture power when the sun is most intense, and then have it available when they need it later in the day, especially after the sun goes down.

This kind of setup allows home storage to act as a substitute for the grid in the same kind of push and pull relationship consumers have under a net-metering model. With net metering, consumer PV systems use the grid as their “battery;” they push to the grid when producing excess power, and draw from the grid when their demand outstrips the immediate capacity of their PV system.

To make local energy storage work, however, consumers need to make sure the system they install can be an effective substitute for the grid. That means a home storage system that is properly sized and configured for the expected demand. Three constraints determine the efficacy of any home storage solution in a “self-supply” or perfect consumption option:

1) The size of the battery

While this may seem an obvious consideration, it’s often overlooked. The battery needs to be large enough to take in much of the power captured by a PV system during the day and also large enough to supply a meaningful amount of electricity later, when the consumer needs it in the home.

Some batteries just aren’t sized for perfect consumption. For example, the Tesla Powerwall, when used daily as a storage battery, can hold 6.5 kWh. Most PV installations in Hawaii and California – two of the leading solar states for residential installations – now average approximately 7 kilowatts peak (kWp), meaning they can fill this battery in less than an hour during peak sunlight. The rest of the power produced by the PV must be dumped to the grid, which is anathema to the goal of perfect consumption (and, under the new Hawaii tariff, will not be allowed).

2) The inverter-charger

This piece of hardware converts the DC current from a PV system to AC current to charge the battery. Inverter-chargers have a maximum rate at which they can convert electricity. Not infrequently, the inverter-charger installed in a home storage system hasn’t been optimized for the PV system or the battery. So a homeowner with a 7 kWp PV installation may well have an inverter that’s limited to 5 kW, which means that the system will fail in capturing and transferring the full supply of energy from the solar panels.

3) The charging rate of the battery, also known as the C-rate

A battery with a C-rate of 1.0 can discharge its entire capacity in one hour. An 11 kilowatt-hour (kWh) battery with a C-rate of 1.0, therefore, can provide 11 kW of electricity for an hour. A lower C-rate reduces the level of power that the battery can provide compared to its size; a higher C-rate increases it.

Looking again at the Tesla Powerwall battery, with its C-rate of just under .5, the battery’s output and charge rate is limited to less than half of its effective 7 kWh size per hour. By contrast, the C-rates on Sunverge battery systems, which are near 2.0, can get users closer to perfect consumption.

But even with larger C-Rates, the battery must be sized correctly—bigger is generally better. Batteries, of course, grow more expensive with size, so it’s also important that home energy storage systems include a software management platform that will balance power loads to most efficiently run appliances and heat and cool the house. That way, consumers get the most out of the battery and don’t wind up buying more than they really need.

As utilities in California, New York and Maine, among others, follow in Hawaii’s path and dial down or cap net metering, getting closer to perfect PV consumption will be an important test for the solar industry.

Outside the United States, pushing toward perfect consumption is even more critical, because so-called feed-in tariffs, which limit the rate at which consumers can be compensated for power they push to the grid, are already in place. In Australia, for instance, subsidies that paid consumers more for their power than the standard grid price, are expiring. With a solid base of PV already installed, the demand for storage in Australia is set to sharply increase.

In Ontario, Canada, the government is set to introduce net metering rules in 2017 that will encourage more self-consumption of solar power, which will require more on-site storage for homes and industry. Before that happens, an Ontario-based utility pilot program will place Sunverge storage and cloud-based energy management systems at 20 homes in the province, which will be optimized for a future where the mission of perfect consumption will become synonymous with PV-generated power.

December 7, 2015 3 comments

Other Renewable Energy

HSBC To Invest $1 Billion In Green Bonds

by Guest Author November 17, 2015

written by Guest Author

Some of the leading global banks and financial institutions are making a beeline to expand their presence in the rapidly growing global green bonds market.

British banking giant HSBC has announced its pledge to invest $1 billion in green bonds, committing to invest in “high quality liquid assets” through green, social, and sustainability bonds. The bank has also stated that it will only invest in bonds that are aligned with Green Bond Principles. The bank will look to finance projects in various sectors including renewable energy, energy efficiency, clean transportation, and climate change adaptation.

HSBC is a member of several associations and bodies working in the climate finance sector, such as the ICMA Green Bond Principles Executive Committee, Green Growth Platform Financial Advisory Council, and the Climate Bonds Initiative. HSBC is already among the leading participants in the green bonds market. According to the Climate Bonds Initiative, HSBC is the 6th largest underwriter this year in terms of assets covered. The bank has underwritten over $1.5 billion worth of bonds during the first three quarters of this year.

Earlier this year, the bank’s Indian arm announced that it will soon launch green bonds in the country. HSBC India Chairman Naina Lal Kidwai recently announced that the bank will launch green bonds to raise funds for environmentally sustainable projects, and noted that HSBC is the world’s fourth largest issuer of green bonds, and now looking to tap the Indian market as well.

November 17, 2015 0 comment

Going Solar PV Rooftop Solar Science Solar $Solar Modules Solar Records

Do Panasonic & SolarCity Announcements Herald Beginning Of Solar Without Subsidies?

by Guest Author October 12, 2015

written by Guest Author

Originally published on The Handleman Post.
By Clayton Handleman

Not so long ago, Sunpower’s 20+% efficiency modules were seen as high end niche products. Last week SolarCity announced that it had leapfrogged that benchmark with its 22% modules currently rolling off of its 100 MW lines and soon to be rolling off its 1 GW line at Elon Musk’s ‘other’ gigafactory. With multiple vendors at GW scale with above 20% efficient modules, PV has reached the point of commoditizing high efficiency modules, and the ripple effect on system level costs has profound implications.

SolarCIty-Truck-1-570x330 Adding fuel to the fire, in a recent Cleantechnica post, Panasonic shot back with its announcement of production prototypes testing at 22.5% efficiency. And the longtime leader, Sunpower, is in the process of upping its game with 23% efficient modules planned for production in 2017 in its Fab 5, which at a planned 800MW (.8GW) is also at the GW scale and rivaling SolarCity’s fab in capacity.

The importance of these announcements cannot be underestimated. SolarCity has long stated that its plan is for its residential PV systems to be cost competitive without subsidies by the time US tax credits expire. Low cost, high efficiency modules offer the path by reducing the physical size of solar arrays and the size-related costs. The benefits of high efficiency include reduced footprint and reduced balance of system costs on a dollars per kW/hr basis and amortization of fixed costs over a larger system capacity.

Many residential systems are limited by roof space, not desired capacity. And a substantial fraction of the cost of residential systems is fixed. As such, by increasing the array capacity those costs can be amortized over a larger project. This reduces the cost per watt and therefore the cost per kW/hr. As module prices have dropped, Balance of System costs for racking, wires, etc. are contributing a larger percentage of system costs. Because more efficient modules provide more energy per square foot, they reduce the cost of balance of system components on a dollars per watt basis. This is explained clearly in this article which includes an easily understood graphic showing how the economics play out. And things have only gotten better since it was written. High efficiency modules are coming in lower than $1.00/W, further amplifying the benefits.

The final piece of the puzzle is gigawatt-scale manufacturing to provide high volume and lower price. SolarCity is doing that with its PV gigafactory, and Panasonic has the scale to develop manufacturing on a globally significant level. When Sunpower was the only game in town and it was producing a tiny fraction of the world’s PV modules, it really didn’t matter how much their modules cost, as it had no real impact on the cost of solar globally.

With high efficiency modules soon to be rolling off gigawatt-scale assembly lines, SolarCity’s vision of PV reaching grid parity even as incentives are phased out appears to be coming to pass. And in volumes with global significance. Clearly the industry is rapidly transitioning to greater than 20% efficiency as the new normal, and with it, the brass ring of cost effective solar without subsidies is rapidly coming within reach.

Reprinted with permission.

October 12, 2015 0 comment

Layman’s Guide to the Value of PV Solar

by Guest Author October 5, 2015

written by Guest Author

By Cy Yablonsky: Vice President PowerLutions Solar

The PV Solar Industry is experiencing explosive growth and many homeowners and business owners are being approached by solar companies to buy or lease a solar system. The purpose of this solar guide is to provide consumers with real numbers and objective information so they will be educated on what to expect from installing solar. This guide will explain common terms used in the industry and during a sales presentation.

Solar salespeople commonly present potential customers with the estimated production in kWh (Killowatt Hours) for the solar PV (Photovoltaic) system, and the value of that production by comparing it to the current & projected utility rate. From this analysis a customer’s estimated savings is presented.

Production in kWhs

Size of the system. Solar PV systems are rated by watts. A 10 kW (Killowatt) system will produce 10,000 watts of electricity per hour in rated conditions. These conditions are defined as Standard Test Conditions (STC). Essentially these are laboratory conditions that do not normally reflect operating conditions. The size of the system is the most easily identifiable, and objective, attribute of the solar system’s capability and potential.
The amount of sunlight at the site’s location. Sunlight varies with location and season. Arizona has the most sunlight in the U.S., while Alaska has the least.Shading can have a significant impact on solar production. Shading can come from a nearby roof or a dormer on the same roof. Most often they come from trees. Different seasons and times of the day can complicate matters, since the Sun moving across the sky can cause partial shading. In addition, the Sun is higher in the sky in the Summer and lower in the sky in the Winter. Solar installers have tools to calculate all the shading variables.
Direction of the roof. The Sun is in the southern part of the sky and it travels East to West. As such, South, SouthEast, and SouthWest roofs generally receive the Sun’s exposure. A southern roof orientation is ideal, receiving the maximum exposure of the sun throughout the day and year.
Tilt of the roof and/or panels. Being that the Sun shines at a certain place in the sky, different angles will affect how the sunlight hits the panels. The rays hitting the panels at the most direct angle will create the most production. On average, a 30 degree tilt (7/12 pitch) is optimal.

Example:

A 10kW system at a 30 degree tilt angle facing 180 degrees azimuth with minimal shading in New Jersey will be estimated to produce 13,500 kWh per year.

Value of Production

Add up the billed amount of all the line items that have kWh (NOT the KW, which is the calculation of the maximum amount of electricity that was needed at any given point).
Divide it by the highest kWh amount specified (which is the total usage for that month) That number is the approximate electric rate. There are seasonal changes to the rate but it can be averaged out. The value of the production is the utility rate multiplied by the estimated annual solar production.

Example:

If the utility company is charging $0.16/kWh and the estimate annual production of the solar PV system is 13,500kWh a year then the value of what the solar is producing is $2,160/Year (.16×13,500).

Utility & Solar Rate Comparison

Example:

In our example we won’t calculate the projected Utility Rate increases. If the Lease rate is $0.09/kWh then the annual savings will be $945 ($2,160($0.09×13,500)).

A few things to be aware of:

The percentage that the solar company assumes regarding the projected utility rate increase can affect how much they portray the total savings to be. If one company states a 2% escalation and another says 5%, the one who said 5% will show a much larger amount of savings over the course of the life of the system. They don’t have control over that number, they are just projecting the future cost of utility energy differently.
If one purchased the solar system they can calculate the IRR (Internal Rate of Return) or figure out when the Break Even Point will be and then have free electricity after that. Purchasing the system up front gives an immediate feeling of savings by avoiding a bill. Although the majority of residential systems installed today are through some sort of Lease or PPA agreement, there are many people who choose to purchase a system up front.
Certain states provide solar system owners additional sources of revenue through REC or SREC (Solar Renewable Energy Certificates) programs. Someone who purchased a system, or receives the SRECs through their lease, earns a credit for each 1,000kWhs produced by the system. They are then able to monetize those credits through various mechanisms that the states setup. This can have a significant positive effect on owner’s cash flow.

Example:

13,500 will produce 13.5 SRECs (assuming the half a credit will be split over two years). If these SRECs are selling for $100 then the total revenue from the SRECs will be $1,350 for the year. In many States these SRECs can fluctuate in price, contracts for a multiyear setprice are sometimes available.

A purchase can also benefit from tax incentives, state rebates and other benefits that are dependent on the location.

October 5, 2015 0 comment

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