About Solar Energy - Today's Most Popular Renewable Power Source
Solar power is the most popular renewable energy source today. People like it because it's an ecologically sound solution to our energy needs. It's clean, it's safe, it's quiet, and virtually maintenance free. It's also being produced in many more attractive forms and styles today allowing it to blend into your roof and building's architecture.
And now, Solar Power is more affordable than ever before. There are many government incentive programs and tax rebates that dramatically reduce installation costs and favorable regulations that require the power company to credit you for excess power that you generate.
What is solar power?
Solar power is power derived directly from the Sun's energy or "solar energy." What is solar energy? The Sun is a primarily a huge fireball composed of super heated hydrogen. The energy from the burning hydrogen travels to the earth in the form of electromagnetic radiation sometimes described as subatomic particles of energy called photons. We see it in the form of visible light and feel it as heat in the form of ultra-violet radiation. Solar power systems capture this energy and convert it to forms that are useful for everyday purposes.
Types of Solar Power Systems
There are two basic solar technologies that are widely available on the market for homes and businesses: photovoltaic and thermal. The most popular technology is photovoltaic which converts sunlight directly into electricity to supplement or replace electricity from the electric company. Most thermal systems on the market today, trap heat from sunlight into a contained area to heat water, and are commonly used to replace or supplement gas or electric for heating hot water in the home or for heating swimming pools.
How does a photovoltaic (PV) system work?
Solar is a simple, elegant technology that is virtually maintenance-free due to the fact that it has no moving parts. The energy source - sunlight - is reliable, locally available, and always free.
A solar electric system is composed of just a few major components - photovoltaic (PV) panels (the generator of electricity) and an inverter (a power conditioning unit). With a grid-tied solar electric system, your system is connected to the local utility grid, which serves as the energy storage and backup for the solar power you generate.
During the day when the sun is shining, your PV panels are generating electricity, and if you are not home to consume the electricity, it is fed through the meter to the utility grid and your meter actually spins backward, banking a credit for you. Later in the evening when you return home, you use electricity from the utility grid and your meter spins forward utilizing the credit you accrued during the day. The utility company is required to credit you for the amount of electricity your system contributes to the grid at the retail value of the electricity at the time it was generated. By properly sizing your solar system to cover your electricity usage, you can eliminate your electric bill and you won't have to pay an electric bill again for the life of the system.
Is there any difference between the electricity supplied by a PV system and the electricity that comes from the power company?
No. A PV system produces power in the form of direct current (DC), but a device called an inverter is used to transform it into alternating current (AC), to match the same type of current that comes from your power company. The electricity to your fixtures, appliances and wall outlets does not change.
How do I know if a PV system is right for me?
There are multiple factors that when taken together, determine whether a PV system will be a good choice for your power needs. They may be thought of in the major categories outlined below:
Regional Factors
Rebate availability, utility rates, and average sunshine in your location are important variables in the payback time for a system.
- Rebate Availability - Rebates range from 10% to 60+% depending on your location and are provided by a variety of sources including the federal government, state government, and utility companies. Check The Database of State incentives (DSIRE) for rebates available in your area.
- Electricity Prices - Local electricity prices have a large impact on system payback times. With utility rate caps expiring in many locations and fossil fuel prices rising dramatically, electricity prices for many residential customers are approaching cost parity with solar electricity.
- Insolation - The amount of sunshine in your location, referred to as insolation, affects the efficiency of the system, and is measured in "full sun hours" per day. Most of the continental U.S. has what is considered good insolation, assuming an appropriate mounting site. Check this insolation map to estimate the solar resources in your area.
Site-Specific Factors
Your site must be appropriate for a solar energy system, including having a south-facing area that receives full sun.
- South-Facing Mounting Area - Your site should have a south-facing area of sufficient size, either for a top-of-pole mount or roof-mounted system, to position the system for maximum efficiency. For example, a typical residential system with a capacity of 6 kilowatts requires approximately 500 square feet of roof space to install. East and west facing roofs can also provide a good mounting area for PV, assuming other regional and site-specific factors are favorable.
- Shade & Obstructions - The mounting area must be free of shading and obstructions. The single biggest obstacle to solar site feasibility is shading from trees and obstructions. Shade cast on the mounting area during full sun hours can dramatically reduce efficiency of the system, and in turn the payback time. Check Google Maps satellite view to confirm shading problems at your site from satellite photos of your area.
- Structural Condition - If installing a roof-mounted system, the roof must be capable of supporting the system, and should have any needed repairs completed prior to installation.
- Power Infrastructure - Homes and buildings with older equipment may require wiring and breaker panel upgrades or expansion, which can affect the total cost and payback of a system.
- Net Metering Rules - Net metering enables customers to offset their consumption over a billing period by allowing them to sell excess power back to the utility provider at the retail rate. There are net metering rules in place for solar power systems in 41 states and D.C. Without net metering, a second meter is usually installed to measure the electricity that flows back to the provider, with the provider purchasing the power at a rate much lower than the retail rate.
- Conservation Measures - Energy conservation measures that economize your home's or facility's energy use can often make the difference by reducing the size of system required. Conservation measures could include using solar attic fans, efficient light bulbs, installing energy efficient windows and power control devices.
Individual Needs
Your power usage and other requirements must be considered when designing and installing a system.
- Power Consumption - The amount of electricity you use, measured in kilowatt-hours, determines the size of the system required. Usage patterns and power requirements vary depending on energy efficiency of the building and appliances, as well as the number of inhabitants and their energy usage patterns. Your power consumption should appear on your monthly utility statement (in kilowatt-hours). Check the system size you need.
- Energy Production Goals - Solar power systems are modular and can be designed to meet all or portion of your energy consumption.
- Aesthetics - Solar collectors come in a variety of sizes and form factors, each with differences in appearance. Product categories include solar panels, integrated roof panels, and solar shingles.
Eclipse Solar, the premier Delaware renewable energy contractor, utilizes the latest technology to reduce energy bills. Call Delaware's own Eclipse Solar at 877-570-3224 or contact us for a free renewable-energy estimate.