Archive for June, 2009

What Size PV System do I Need?

Matching Your Load With Your PV System

If you have determined that PV is the best way to meet your energy needs, you need to size your system to effectively meet your daily load. You will need the answers to the following questions and the assistance of an expert to make an informed decision.

What is your budget? Remember, in New Jersey and many other states, the government offers rebates and tax credits at the federal and state levels. It is cheaper overall to install a larger system all at once than to only add a few kilowatt system and add later. A 10 kw system is generally required to qualify for net metering, and for registration online to earn SRECs.

Does your load need to be met all day every day? If not, what percentage of your energy needs do you hope to supply with your system?

Will you need to stay hooked into the grid if there are extended periods when the sun does not shine? New Jersey and surrounding states can experience periods of cloudiness for days, especially in winter.

What are has your average electricity usage been over the past few years?

Does your utility company allow net metering (will they let you have energy when you need it, and buy back from you when you have excess)?

Once you have determined what your budget and expected usage are, you can calculate the size system you should purchase. A chart is available for calculating square footage of roofing needed by the efficiency of your proposed PV modules here.

Your first step is to determine your average daily usage in kilowatt hours. Most bills will have this displayed either as a daily average over the month or the total kilowatt hours used over the month. Look at your average over the year to get the best estimate of your usage.

Use the chart found here to estimate the number of clear, partially cloudy and cloudy days per year in your state or town. This will give you an idea of how much monthly production you can have at different times of year.

Arosa Solar can help you estimate the size PV system you will need to produce any percentage of your building’s energy. You can work the figures backwards if you are buying based on a budget, multiplying the number of sunlight hours / day times the number of kilowatts a prospective system would produce. This will give you an idea of what percentage of your home’s power could be replaced with solar energy on an average day.

Go solar!


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Easy Ways to Save Using Solar Energy

Summertime has arrived in New Jersey, and energy costs are on the rise. Running the air conditioner makes many people cringe, as it drives up energy consumption and bills. For those not yet able to make the full leap to completely solar driven power usage, solar attic fans can help decrease the level of energy needed to keep your home cool.

Solar Attic Fans

Solar attic fans can decrease the cooling load on your air conditioner. They increase fresh air circulation, keeping your roof and attic space cooler and extending the life of your roof. They come on when the sun is out and heating up your roof and attic, so they only work when needed to cool down the worst of the hot air.

Two fan options are generally available with adjustable solar panels. The 10 watt ventilates 1200 sq feet and the 20 watt covers 1800 sq feet. Installation costs range between $475 to $600, and most fans will pay for themselves in just a few years by reducing energy needs and prolonging the lifetime of most roofs.

Solar Tube Lighting

Solar tube lighting can be a tremendous money saver at any time of year, bringing natural lighting into your home or business. Installed lights range from approximately $350 to $600. The expense is worth it, as they will pay for themselves over time by reducing costs from electricity and standard light bulb purchases. The highly reflective light pipes can be up to 18-20 feet long, and are made of high grade aluminum with seamless construction.

Tubular skylights are smaller than most other skylights. They have roof-mounted solar collectors, which increase their daylighting potential even with their small size. Since a rooftop solar collector has such a small surface area, tubular skylights minimize heat loss in the winter and heat gain in summer.

The diameter of the tube determines the coverage area. A 10 inch solar light will cover up to 150 sq feet, and provide the equivalent of up to 300 watts. A 13 inch tube has a coverage of 300 sq feet, with about 500 watts. A 21 inch light covers 700 sq feet and delivers up to 1450 watts.

Both of these options can help you keep energy costs down. Contact Arosa Solar and talk to an expert about how you can save money by using the clean, renewable energy of the sun.

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Solar Thermal Pool Heating

It’s June! Right now the water is your cool haven from the heat – but when cooler weather comes at night is it too chilly to enjoy your pool? The cost of heating a pool can severely limit the swim season in the northern US particularly. However, you can enjoy all the benefits of pool ownership for a broader season each year, regardless of cooler weather.

Although operating a standard gas or electric heater can cost hundreds of dollar per month, a solar heater will warm your pool free day after day, using the clean, renewable power of the sun. This saves money over time, and eventually pays for itself in savings!

Solar pool panels come in a variety of sizes. You can have them mounted on a nearby roof, or even on the ground. Arosa Solar makes installation easy; it can usually be completed in one day, so you can enjoy the benefits of solar-heated water right away. Solar pool-heaters are made of a flexible polymer material, and include an electronic controller, an automatic diverter valve and special sensors for temperature control.

Your existing pool pump is probably strong enough to run the solar swimming pool heating system. It will send the water up pipes to the solar collector. As cool water enters the solar collector at the bottom, it is heated. It then makes its way up through the collector tubes to the top header pipe. The comfortably warm water is then returned to your pool! This process repeats until the desired water temperature is reached, keeping your pool warm even on chilly nights.

Even pools with an existing electric or gas heater can be enhanced with a solar heater. The system is remarkably efficient and virtually free to operate, so it can significantly reduce your energy costs and pay for itself over time. Installing a solar pool-heating system also adds value to your home, as does any renewable energy system.

If you already have an existing solar hot water system adding a pool heater is simple. Using clean sun generated power can give you all the hot water you need for home and pool, reducing your environmental footprint and lowering your energy costs by up to 38%!

You can contact an Arosa Solar Energy Specialist in New Jersey or online today for a free consultation and to learn all about the solar benefits available to you.

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