Frequently Asked Questions

Is energy stored in Solar Cells?

No. Solar cells just convert sunlight into an electric current that must be used immediately or stored in batteries for later use.

Do solar panels work in cloudy cold weather?

A cloudy day provides sufficient diffuse light by which the panel will produce electricity. Optimum electrical production occurs with bright and sunny weather conditions. Under a light overcast, the modules might produce about half as much as under full sun, ranging down to as little as five to ten percent under a dark overcast day. In remote, off-grid applications, a PV system is connected to a battery storage system as a backup power source. In grid-connected applications, the PV system works in parallel with the utility power grid. So, if electrical needs exceed the solar power output, the local utility makes up for the shortfall. Conversely, when the PV system generates more energy than the building requires, the excess power is exported to the utility grid, reversing the electrical meter!

Do Solar Panels work in the winter?

Solar panels work on light not heat. With shorter daylight hours in winter, solar panels produce proportionately less power. If the modules become covered with snow, they stop producing power, but snow generally melts quickly when the sun strikes the modules; if you brush the snow off, they resume operation immediately.

Do Solar Panels require a lot of maintenance?

Solar panels benefit from a non-abrasive cleansing agent. When reviewing battery levels, check battery connections and fuse holders to ensure that they are clean and dry. If necessary, use a silicon sealant for sealing damages around the frame. Although the production of solar panels incorporates a high-tech manufacturing process, it’s really very easy to use a photovoltaic system. Solar panels have no moving parts to wear out, they can be used alone or in combination with other energy sources, and they are silent, reliable and long lasting.

What is the difference between solar thermal and solar electricity?

Solar thermal usually refers to using the sun to heat water. So, you place solar panels on your roof and they heat the hot water in your hot water heater and you take a shower, do your laundry, cook, clean etc..with water which has been heated by the sun. This usually saves you 30% on your electrical or gas bill! It is a huge savings with the quickest return on your investment (paying off in 2-5 years). Solar PV, (photovoltaic) or Solar electrical is using solar panels to power your homes electrical needs via on the grid or off the grid. On the grid power simply means you are connected to the local utility company but don't really use them for electricity, you use your solar and feed them back electricity for credits. You also have them for an emergency power need that your solar battery backup can't help with (say a 10 day blackout ).

How expensive is solar right now with rebates?

The cost of a solar energy system depends mainly on its size---that is, on the number of watts of power it can produce. The size of your roof, lot or budget may dictate the maximum size of your system. The average residential system now costs about $8 to $10 a watt installed. A small, energy efficient house may be able to offset all of its electrical load with a 2.5 kilowatt system, and at $8 a watt the system should cost about $12,600 after tax rebates. The trick is to find local and federal incentives and rebates to drive that cost down. The federal solar investment tax credit equals 30% of the system cost for a residential system; up to $50,000 for a commercial installation. The Utah State tax credit is $2,000 for residential and $50,000 for commercial systems. For a complete list of tax incentives in your area click on the link www.dsireusa.org .

What are the basic parts to a solar panel system?

A standard DC system that will only run appliances and DC lights, (much like what you see on boats and RVs) can cost as little as $150-$200.00. Many cabin owners, boat owners and RV owners get started this way. You basically need 1 Solar Panel and 1 12 volt Battery. When that same cabin owner decides it ts time to upgrade, he/she will need to covert the DC power to AC using an inverter. An inverters job is to convert the DC power to AC so smaller appliances & lighting (like the TV, Radio, Lights) work. Inverters are priced by how many watts they run. Now, when that same cabin owner decides to upgrade again to a larger system, he/she must now purchase multiple solar panels, multiple batteries and a larger inverter. Roof mounts, wire, monitoring software and meters will also be purchased.

What is CSP-concentrating solar power?

CSP plants use what is called focused sunlight. CSP plants generate electric power by using mirrors to concentrate (focus) the sun's energy and convert it into high-temperature heat. That heat is then channeled through a conventional generator. The plants consist of two parts: one that collects solar energy and converts it to heat, and another that converts the heat energy to electricity. Within the United States, over 350MW of CSP capacity exists and these plants have been operating reliably for more than 15 years.

How do solar thermal systems work?

A: Every solar water-heating system features a solar collector that faces the sun to absorb the sun's heat energy. This collector can either heat water directly or heat a "working fluid" that's then used to heat the water. In active solar water-heating systems, a pumping mechanism moves heated water through the building. In passive solar water-heating systems, the water moves by natural convection. In almost all cases, solar water-heating systems work in tandem with conventional gas or electric water-heating systems; the conventional systems operate as needed to ensure a reliable supply of heated water.

What is an inverter?

The inverter is the heart of all but the smallest power systems. It is an electronic device that converts direct current DC power from batteries or solar modules into alternating current AC power to operate lights, appliances or anything that normally operates on power supplied by the utility grid. Inverters come in many varieties, sizes and qualities and offer various features that specialize them for particular applications.

How much water can be pumped using a solar water pump?

Each pump generates a different amount of gallons per minute ranging from 1 gpm to 75 gpm. If you are pumping from a well we recommend the SQFlex which can lift water over 600 feet and pump over 20,000 gallons per day at lower lifts.

Where can I pump my water with a solar water pump?

A surface pump can draw water from a dug well, spring, pond, river or tank, and push it far uphill and through a long pipeline to fill a storage tank or to pressurize it for home use or for irrigation, livestock, etc. The pump may be placed at ground level, or suspended in a well in some cases.

Does the water pressure ever drop or suffer when using a water solar pump?

Yes. Typically households use conventional AC powered water systems which pump from a well or other water sources, into a pressure tank that stores water and stabilizes the pressure for household use. However, this will not work with pumps operating directly from PV modules because the sun may not be shining when you need pressure and thus the pump may not keep up with household use. There are two ways to solve this problem. A non-pressurized water tank can be located high enough above the house for gravity to supply the water pressure. This can be on a hill or a tower. The second solution is to have a battery operated pressure booster pump which can fill a pressure tank as needed from a storage tank that is filled by a solar pump during the day.

How much power from an inverter do major appliances require?

Standard AC electric motors in washing machines, larger shop machinery and tools, swamp coolers, pumps, etc. (usually 1/4 to 3/4 horsepower) require a large inverter. Often, a 2000 watt or larger inverter will be required. These electric motors are some- times hard to start on inverter power, they consume relatively large amounts of electricity, and they are very wasteful compared to high-efficiency motors, which use 50% to 75% less electricity. A standard washing machine uses between 300 and 500 watt-hours per load, but new front-loading models use less than 1/2 as much power. If the appliance is used more than a few hours per week, it is often cheaper to pay more for a high-efficiency appliance rather than make your electrical system larger to support a low-efficiency load. Vacuum cleaners usually consume 600 to 1,000 watts, depending on how powerful they are, about twice what a washer uses, but most vacuum cleaners will operate on inverters larger than 1,000 watts since they have low-surge motors.

What happens if I have excess amounts of power from my solar power systems?

In many states, you can send your home-generated power back to the utility and get credit for the power you feed into the utility grid.