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| What are Photovoltaics? |
Photovoltaics are solar cells that produce electricity directly from sunlight. They are usually made of silicon-the same material that makes up the common beach sand. The cells are wafer-think circles or rectangles, about three to four inches across. Solar cells operate according to what is called the photovoltaic effect, ("photo"-light, "voltaic"-electricity). In the photovoltaic effect, "bullets" of sunlight-photons-striking the surface of semi-conductor material such as silicon, liberate electrons from the material's atoms. Certain chemicals added to the material's atoms. Certain chemicals added to the material's composition help establish a path for the freed electrons. This creates an electrical current. Through the photovoltaic effect, a typical four-inch silicon solar cell produces about one watt of direct current electricity. |
| How are photovoltaic cells made? |
In the most common cell production process, very pure silicon is reduced to its molten form. Through a painstaking and time-consuming process, the silicon is re-formed into a solid, single-crystal cylinder called an ingot. Extremely thin slices cut from the ingot are chemically treated to form photovoltaic cells-sometimes referred to as solar batteries. Wires attached to the negative and positive surfaces of the cell complete the electrical circuit. Direct current electricity flows through the circuit when the cell is exposed to light. Silicon photovoltaic cells convert sunlight directly to electricity. For efficiency and practicality, multiple cells are wired together in a series/parallel fashion and placed in a glass-covered housing called a module. The modules themselves can then be wired together into arrays. PV arrays can produce as much direct current electricity as desired through the addition of more modules.
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| Can PV modules power regular appliances? |
Photovoltaic modules and arrays produce direct current (DC) electricity. Because most appliances and equipment are designed to be powered by alternating current (AC), PV-produced electricity must be converted. This is accomplished by an inverter. Most of these solid state devices convert DC current to an AC current compatible with that sent over utility grids. As a result, PV installations may be interconnected with a utility grid, sending power onto the grid whenever there is an excess, and drawing electricity from the utility when sunlight is not available. Most inverters have a fail-safe relay that disconnects the PV system from the utility grid whenever the grid fails, ensuring the safety of utility repair personnel.
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| What are the current uses of Photovoltaics? |
Many remote uses of Photovoltaics are cost-effective and practical now. Photovoltaics are generating power for both on-and off-shore traffic control systems, crop irrigations systems, bridge corrosion inhibitors and radio relay stations. They are also providing electricity to remote cabins, villages, medical centers and other isolated sites where the cost of Photovoltaics is less than the expense of extending cables from utility power grids or producing diesel-generated electricity. |
| What is a solar water heater? |
A solar water heater uses the sun's energy rather than electricity or gas to heat water, thus reducing your monthly utility bill. When installed properly, solar water heaters are more economical over the life of the system than heating water with electricity, dedicated heat pumps, heat recovery units or propane. The direct circulation system circulates potable water from the water storage tank through one or more collectors and back into the tank. The solar collector is the main component of the solar system. It is usually a box with insulation and a black absorber plate that collects solar radiation and heats the water. In integral collector storage systems, the solar water storage system is built into the collector. The potable water in the collector unit is heated by the sun and delivered by city or well water pressure to an auxiliary tank (which contains non-solar back-up heating) or directly to the point of use. A thermo siphon solar water heating system has a tank mounted above the collector (normally on the roof) to provide a natural gravity flow of water. Hot water rises through piping in the collector, which is mounted below the tank; heavier cold water sinks to the lowest point in the system (the collector), displacing the lighter hot water which rises to the tank.
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| How does a direct circulation solar water heater system work? |
As sunshine strikes the collector, the water inside it is heated. During periods of insufficient sunshine or high hot water demand, a backup electrical element in the storage tank heats the water. The check valve prevents heat loss when the circulating pump is off or with the flow of water mounted over the collectors. |
| What size solar water heater system do I need? |
For a family of four, 2500x1500x2500mm of collector and a total tank storage of 125 ltrs. are typical. It must be noted that thermo siphon systems will include two tanks, the solar system tank as well as the auxiliary tank. Add on Solar systems electrically-assisted can also be procured ,electrically-assisted system that uses a 2 K.W or 3 K.W electrical loads retrofitted. which can be useful for the non sunny days or increased demand for hot water supply.
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| How much do I save? |
Your monthly savings will depend on the amount of hot water you use, storage tank size and type and price of fuel used for backup water heating . For a family of four, the typical hot water usage is 100-litres per day, thus using 1530-kilowatt-hours per year to heat the water electrically, or Rs.7420/-(considering 300days for usage) per year worth of electricity at Rs.4.85/- per kilowatt hour. A solar water heater should save between 50% and 85% of the hot water portion of the monthly utility bill, or Rs.7500/- to Rs.8500/- per year for a family of four. A solar water heater can save even more if you turn off the backup and rely solely on the sun for your hot water. During summer months, when hot water demands are lower and the sun shines longer, most solar owners turn off the backup element circuit breaker, or switch. As electricity and other fuel prices go up, solar savings will increase accordingly. |
| Do I have to change my habits to use a solar water heater? |
No. Solar water heaters could always be installed with a backup heating system in the storage tank to ensure that hot water is available at all times. However, to maximize solar utilization and your savings, you should attempt to use the most hot water in the late morning and early afternoon when the solar system is operating at its peak due to the available sunshine. Also, your solar system will be more effective if your use of hot water is spread more evenly over the week . For example, if you use hot water for laundry, instead of washing seven loads of clothes in a single day, wash one load each day. This will reduce the amount of backup energy required for your solar system. |
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Solar Energy: Benefits |
Your home is probably your most significant purchase ever. Solar water heating adds significant value because it provides clean, clear, hassle free offering unsurpassed comfort and security. And because it gives you a higher level of energy independence, it offers your family even more peace-of-mind. |
Free power from the sun |
Unlike most conventional power sources, once you install an Solar water heating system, there are no additional fuel costs. It just keeps on working. Every day the sun comes up, you're generating your own "free" power. No one can raise the price of sunlight! And it's the most reliable and cleanest source of energy on earth . |
No fuel, no emissions |
Reduce or eliminate your electricity bills. Guard against rising energy rates. Add comfort, security and value to your home. Protect the environment. Ensure that you have power, even when your neighbors don't. Put yourself in control of your energy future. while you're reducing air pollution and global warming. |
A Bright Future |
Government of India offers 80% depreciation claim in the first year itself on installation of commercial solar water heating systems.
A solar water heater is a long-term investment that will save you money and energy for many years. Like other renewable energy systems, solar water heaters minimize the environmental effects of enjoying a comfortable, modern lifestyle. In addition, they provide insurance against energy price increases, help reduce our dependence on foreign oil, and are investments in everyone's future. |
Environmental Benefits |
When a solar water heater replaces an electric water heater the cost of electricity goes down even Solar water heaters do not pollute. By investing in one, you will be avoiding carbon dioxide, nitrogen oxides, sulfur dioxide, and the other air pollution and wastes created when your utility generates power or you burn fuel to heat .your household displaced over 20 years represents more than 50 tons of avoided carbon dioxide emissions alone. Carbon dioxide traps heat in the upper atmosphere, thus contributing to the "greenhouse effect." |
Do the right thing. Do it today |
Now is the right time. Do the right thing.for your kids.for your community.for your country and the world. Call for a Solar Water Heating System today, and schedule an at-home consultation. Leave it to us, we make getting solar power easy. |
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info@solar-urja.com
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