In Focus: Calculating Monthly Solar Savings


Solar Installers get a lot of calls from consumers who are unsure how to work out how much their solar power system is saving them.

The most common mistake made by consumers is to open their power bill and assume that their system has only saved them the amount of the credit that is listed on the bill. This approach does not measure the full value of the savings because it does not measure the solar power that was generated on the roof and consumed in the building before it was recorded on your meter.

Working out a return with 1:1 Net Metering

Working out the true return is a relatively easy process in areas where there is 1:1 net metering, where your utility pays you the same retail price for excess solar power that is fed into the gird as you pay when you buy power from them (either at night or when your solar generation during the day is less than your consumption). In this instance, you simply need to multiply the kwh of power produced for the month by the retail price you pay for power.

However, even this simple calculation can be more difficult than it appears. Firstly, inverters generally have a display that can show energy produced today and energy produced for all time, but not a display that shows energy produced for a particular month. The only way to get this information is to either install a monitoring system that logs this data or manually recording the “Energy Total” reading each month. The second difficultly in working out even this simple calculation is that the amount most people pay for power varies with usage so, for example, a consumer in California might pay 14 cents per kwh for their first 100 kwh per month but pay 20 cents per kwh for power used in excess of this amount. (just an example)

When calculating the value of the savings that your solar power system has delivered, make sure to use the value of power for the most expensive units of power that you have purchased during a period.

The reason for this is that if you did not have a solar power system, and therefore had to buy additional power, all of this additional power would need to be purchased at the top rate. In some cases, the power may have to be purchased at an even higher rate if extra consumption pushes you into a higher pricing band.

Working Out a Return Where There is Not 1:1 Net Metering

Where there is not 1:1 net metering, you will need to work out your return in two parts, because the solar power you generate has a different value to you depending on whether it gets used in your house or exported to the grid. This means you firstly have to work out what part of your total solar power production was used in the house and what part was exported to the grid. You can usually get the amount of kwh that was exported to the grid from your power bill. Simply multiply the number of kwh by the rate you get paid for solar power exported to the grid and you have the savings you got from the power that was exported.

Getting the savings from the solar power that was used in the house is harder because as stated above most inverters don’t have a display on monthly energy output. To get this, you either need to record the Energy Total number from your inverter on a set day each month or have a monitoring system installed that allows the display of this data. Once you have this figure then you need to deduct the kwh’s that were exported to the grid (from your power bill) to get the kwh’s of solar power used internally.

Solar Power Consumed Internally = Change in Etotal on Inverter During the Period – Power Exported to the Grid During the Period

by Andy Sendy, Owner of Solar Wholesalers an installer of solar panels in Adelaide, South Australia

Original Article on SolarReviews

Weather and Solar Panel Performance


Here at SolarReviews, we’ve received quite a bit of questions centered around the performance of solar panels under different climate conditions – and so it’s only within our nature to answer a few of them.

What happens if there’s a snowstorm? Typically, it’s strongly advised that you choose a spot on your roof that is least affected by snow – though, we understand that during a snowstorm, this could virtually be impossible to avoid. Don’t worry – as many solar panels are dark enough to retain heat that the likelihood of snow melting off them is much quicker than you’d think.

Can my solar panels survive hail? This may be the most asked question we receive. According to Rich Hessler, a Californian photovoltaic specialist, a hailstone hit at speeds of up to 120 mph rarely translates as a solar power system killer, as long as the module’s frames don’t collapse and glass fragments don’t damage the cells. Most solar panels are tested to endure a direct hit from a hail stone 1″ or smaller at 50+mph. In the U.S., most hail storms come from the north, with solar panels facing south, which means they can endure larger sized hail stones with a glancing blow. In other words, solar panels are quite resilient to hail, although you’ll want to make sure your solar panels are covered as a part of your homeowner’s insurance policy.

What if I live in an area with high winds and hurricanes? Solar manufacturers make sure that they design solar panels to withstand high winds. If you live in an area that’s prone to hurricanes, your insurance company will require that you have “hurricane proofing” for your solar panels. Also know that should any damage occur, solar manufacturers have warranties and you should have homeowners insurance to help with any repairs, as needed.

How effective are my solar panels in other weather conditions such as fog and rain? As highlighted by Residential Solar 101, under cloudy and rainy weather conditions, your solar  panels drop 40% – 90% depending on how dark and heavy the rain and clouds are. Now, if we’re to look at fog – know that your solar panels will still work. For example, the amount of power you’ll generate depends on the thickness of the fog; if the cloud cover is at its worst, your panels might produce only 5-10% of the energy they normally do, but a thin layer of fog has much less impact on solar energy output. Even if you live in an area with lots of foggy days, what really matters is how much sunshine your roof receives over the course of a whole year, not on a given day (One Block Off Grid).

Original Article on SolarReviews

DIY Solar: 6 Reasons Not To Do It


The growth of solar power is continuing its trend upwards and so is the amount of promoted DIY solar panel kits out on web. DIY solar panel kits may seem like the ideal solution as you may initially think it’s going to help cut down on cost; however, this isn’t necessarily the case.  Professional solar installers go through a significant amount of training to be experts in their trade, with some even receiving advanced accreditation’s like a NABCEP Certification.

Here are six reasons why you shouldn’t go the DIY solar route:

  1. First, and foremost, you’re likely not qualified to do so.  Would you install your own central air conditioner or furnace, or rewire the electric in your house?  Likely not, you’d leave it up to professionals to do it, which is exactly what you should do with installing solar panels.
  2. The standard life span of solar panels professionally installed by a solar installer is 25 years; whereas, DIY solar panels are said to not last very long and the efficiency will decrease over a short period of time.
  3. Maintenance will be much more demanding and with maintenance comes cost. This isn’t ideal because it could very well turn into a full-time job and you will most likely not get the type of investment you want.
  4. Another initial investment you must make is getting your DIY solar panels certified. This process takes months and can cost you thousands of dollars.
  5. You will have to ensure that the DIY solar panels are safe, getting them inspected by an electrical inspector, as well as complying with any regulations or standards your power company requires. As such, working with a consumer top-rated (and certified) solar installer will help make these processes run smoother.
  6. A small misjudgment of the condition of your rooftop can essentially cost you thousands of dollars in repairs if not inspected properly. Knowing how and where to position your solar panels are incredibly important.

Now, here are some recommendations you should consider before going solar:

  1. Available rebates and incentives in your state.
  2. Research the top consumer rated solar installers in your area.
  3. Choose the right solar installer as it will make your experience a great one.
  4. Decide if you’re going to lease, finance or pay cash for your solar power system.
  5. Research solar power facts, so that you are well equipped to make the best decision for your home

Original Article on SolarReviews

Residential Solar: When Analyzed Properly, Returns are Great


One of the issues faced by consumers when considering going solar is that things are changing so frequently that it is hard for consumers to evaluate solar as an investment.  Solar prices have fallen significantly over the past few years, but government and utility rebates and incentives have been in a perpetual state of change.  These constant changes have meant that it is almost impossible to publish anything related to solar pricing that remains accurate over time.   This has led to most consumers using overly simplistic methods to evaluate solar power as an investment. These simplistic methods fail to give solar electricity the full credit it deserves.

The first thing that is easy to find out about a home solar system is how much power it will produce. This page on SolarReviews allows you to see how many kwh’s (kilowatt hours) per day of electricity you will get from each kw of peak capacity solar you install in your state.  For instance, a 5kw system in Southern California will produce 4.5 kwh x 5kw (size of system) multiplied by 365 (days of the year), or around 8,200 kwh per year.  A consumer in California who is paying 15 cents per kwh for power would most likely think that their return would by .15 x 8,200 kwh per year, or $1230 per year.  If this person was looking at a 5kw system that cost $15,000, after rebates and the federal tax credit, then they would conclude that their return would be 8.2 %.

That is not a bad return, but it is a fair evaluation of the investment in a solar power system?  It may be an accurate reflection of the return on investment in the first year, but not over the life of the project.  The reason this is the case is that energy prices from utilities using finite energy sources will continue to increase over time.  Each time this happens, the same 8,200 kwh per year produced by the solar power system becomes worth more to the owner.

To work this out, you need to use a financial method known as internal rate of return (IRR).  Investors use this type of calculation to evaluate the average return they receive over the life an investment, when the returns from their investment change each year.  Based on the above figures, and based on the assumption that electricity prices will increase 3.5% per year over the 25 year life of the system (some estimate that electricity prices will increase at an even higher rate), the IRR for this system would be 12%.

This is a very good return on a consumer’s investment, and all the more reason a home solar power system can be for your pocketbook.

SolarReviews – a leading consumer reviews website designed to improve the experience for solar installers and consumers.

by Andy Sendy

Paperwork: Dragging The Adoption of Home Solar Power Systems


The average retail  price of home solar power systems is higher in the United States than what it is in other countries that have been significant adopters of solar power.  This prompts the question, why?

While the tariffs imposed on Chinese solar panels in 2012, and the difficulty of installing solar panels on some common roof types, may be part of the answer, there is no doubt that a significant reason is because of the paperwork a solar company, and their customer, must go through to install a solar power system on the property.

There are building and zoning permits that must be obtained, and these vary from county to county, requiring a significant amount of time and money for solar companies and their customers.  In countries where home solar power systems have reached high penetration levels, up to 20% of homes in some parts of Germany and Australia, there are exemptions in place which make it unnecessary to apply for zoning and building approvals for solar projects that would apply to other home renovation projects.  It is notable that both of these countries have per watt retail solar system prices that are significantly lower than in the United States.

Individual inspections are also required of solar power systems by government agencies and utilities in the United States.  These, too, are time consuming to organize and attend and add to the overall cost of installing a solar power system.  We don’t inspect every tank of gas before it is loaded into a car, and it is not necessary to inspect every solar system that is installed.  The reason we don’t inspect every tank of gas that goes into a car is that there are standards in place that ensure the quality of that product.  This is also true of solar power systems in other countries and should be in the case in the United States.

Standards are already in place to govern, both the products that are allowed to be used in solar installations, and also the qualifications a contractor must have to install a system. These licensing standards can be seen here on SolarReviews or in a less concise way on the website.

It is imperative that a similar exemption be introduced in the United States. The solar industry is now economically viable, even with only very modest and affordable levels of government support.  By lowering the burden of regulation, which adds no value and keeps the cost of solar installations artificially high, the solar industry can continue to expand, creating even more jobs in an industry that is rapidly expanding.

by Andy Sendy

Original Article on SolarReviews

SolarReviews: Improving the Solar Experience for Consumers and Installers


SolarReviews, a recently launched consumer reviews website dedicated to the solar industry, has unveiled a customer engagement model designed to improve the solar experience for consumers and installers. Visitors to the website are able to search for installers who serve their area, view installer profiles, read independent customer reviews, and request a solar quote from their favorite installers.

There has been no shortage of lead generation services available to the solar industry, although to date these methods have used an anonymous process, where consumers using the services are given no information or choice about which installers their details are being sent to. As a result of not connecting consumers with their preferred company, installers can experience an inefficient use of sales resources and poor sales close rates, leading to a poor return on investment. From a consumer’s perspective, they are overwhelmed with sales calls from installers that don’t meet their preferences.

The SolarReviews process gives consumers complete visibility of the details and reputation of each installer, which ensures that the installers they choose to request a quote from are likely to suit their preferences. “Consumers are conducting research online now more than ever, and reviews websites are playing a big part of that”, stated Jesse Truax, VP of Marketing and Business Development for SolarReviews. A survey by Search Engine Land found that 72% of consumers trust online reviews as much as personal recommendations.

By giving consumers the ability to conduct research and choose which installer they would like to do business with, SolarReviews will improve the solar experience for consumers, leading to higher sales close rates for installers. Pilot results that led to the development of the SolarReviews process indicated sales close rates that were significantly higher than that of traditional lead generation services. This process is a very positive step forward for consumers and installers and will enhance the overall reputation of the solar industry.

SolarReviews encourages installers, who have not yet claimed their profile, to register on Once registered, installers will have the ability to add/change company information, photos, services, territories, and more. Most importantly, installers can solicit reviews from customers and leverage those reviews to generate solar consultation requests through SolarReviews.