The sun's energy makes it possible for us to live on planet earth. Sunlight is used by plants to convert carbon dioxide into organic compounds, like sugars, which allow the plant to grow. The bi-product of plants' digestive process is oxygen. The presence of oxygen has allowed animal life to evolve on earth. Now that we are at the end of the fossil fuel burning industrial age, there is more energy available from the sun than all the energy that we can dig out of the ground. And this renewable source of energy will be available for the next 5 billion years.
Solar energy or solar power is the conversion of the sun's light and heat into a power source that can be used by humans for transportation, heating and cooling, manufacturing, and most of our other energy needs.
We highlight many of the uses of solar energy, such as solar electric production, solar heating and cooling, uses of solar, solar history, solar water heating, and solar products available today.
The basic building block of a photovoltaic system is a solar cell. It is made of silicon semiconductor material and converts light into electricity. A matrix of solar cells are wired together to make a solar panel, which typically outputs 12, 24, or 48 volts direct current (Vdc). A single solar panel can be used individually for small charging chores such charging a 12 volt battery or charging electronic equipment such as cell phones. However, to supply electricity to a whole household, several or many solar panels must be wired together to form a solar array. This solar array is usually mounted on an equator facing roof top or a metal post. The electrical output of your solar array is totally dependent on the amount of direct sunlight that hits the panels. Any obstructions, such as trees or clouds, will severely reduce the amount of electricity produced.
The sun can very efficiently heat and purify water. Solar water heaters typically use a pump to circulate water through pipe up to a solar concentrator. Cool water from your storage tank is fed into the lower side of the solar water heater. Hot water is pushed out of the top pipe going back the your storage unit. There are many variations on this theme. Some of the more basic designs are better suited for climates that don't have frost. More sophisticated designs are needed for cold weather climates. Find out more here.
Solar home heating refers mainly to good conscientious design to take advantage of the free resources given by the sun. Designing your home so that widest side of your house faces the sun and has appropriate grazing for climate to allow winter sun to penetrate the interior floors, wall, and fixtures is just one of the many techniques for reducing your energy bill. Passive and active solar heaters are another idea that has been well developed, tested, and implemented typically in situations where fuel costs are simply too expensive. Find out more about how to use the sun to heat your home in the winter.
Installing solar energy products is a relatively simple task. Solar panels, for example are much easier to install than a gas powered furnace. Just install the brackets on the roof, snap in the panels, then wire them up. However, when you are ready to tie them to the grid, you'll want to bring in a licenced electrician to meet local building electrical codes. Other types of solar devices are even easier to install. Solar landscape lights on stakes simply push into the ground lining your walkways. No wiring needed. They are plug and play. On our solar installation page, we talk about a number of key issues to consider when planning your solar PV installation. Topics such as sizing the system, cost benefit analysis, and choosing components are addressed in more detail.
Although there are many components to many solar products large and small, most home owners want to know what components they need to build a grid tie solar energy system for their home. There are 2-3 critical components that are a part of every home system. Of course you need PV solar panels. The other critical component of a grid-tie system is an inverter. This device converts the Direct Current (DC) produced by the PV panels to conventional Alternating Current delivered to our homes by the electric utility company. This allows us to power our conventional AC devices such as TVs and refrigerators with our new solar panels. The third mandatory component of the system is wiring and conduit. These are like veins and arteries in the human circulation system, without them, there is no useful electrical production from your PV panels. Two other reasons wiring is so important is that they must be sized to your power needs and their installation must meet National Electric Code (NEC) standards for safety.
Additional components in a good PV system are things such blocking diodes, fuses, dis-connects, and batteries. Use batteries when you want back up power in a grid connected system or when your home is off-grid. More about solar energy components can be found here.
There are dozens of terms used in the solar electric industry that improve your understanding of this valuable and increasingly popular solar energy field. Many of the terms are quite technical and are not unique to the solar industry. For example, some of the terms deal with semiconductor principals such silicon. Some of the terms deal with other physical properties such electronics, battery technology, and the earth's relationship with the sun. Use this glossary as a reference when you are designing your solar energy system.
The many uses of solar energy are endless. You have been using solar energy either directly or indirectly your whole life. Just think of when you got into your car on a sunny but cold day. How much warmer was it inside the car as opposed to outside? We now must actively think about the impacts of using carbon producing tools and replacing them with solar energy tools. Read and contribute to our Solar Uses page and be rewarded with free solar energy.
Using the sun to keep your swimming pool water warm is especially popular in the warm weather states. Most systems use a flat plate type solar water heater mounted on a roof. A pump, which can be powered by solar panels, keeps the water circulating at very low cost. Compared to conventional gas or electric powered swimming pool water heaters, and with rising fuel costs, the payback period is very short. In fact, in cities such Las Vegas, Nevada there are no new swimming pool installations that don't some form of solar water heating. Many previous pool installations are being converted to solar in large numbers. In 2010, 35,464 solar water heating systems and 29,540 solar pool heating systems were installed nationwide. In the mist of a deep recession, it's a growth industry.
In cold weather states you can build your swimming pool inside a greenhouse like structure with large winter sun facing glazing to minimize the need for fossil fuel water heating. If the greenhouse is attached to your main house, this type of design can also help keep the house warm in the winter. Find out more about solar pool water heating here.
With the price of solar panels dropping rapidly, imagine entire cities being powered by solar energy. Not only that, what if these cities could integrate solar PV panels into all aspects of modern architecture. That is what is happening now in Hinin, China. Check out this cool video.
Tags: solar energy, solar panels, Solar heating, photovoltaics, solar power, alternative energy