POWER GENERATION- Solar, Wind, and Micro-Hydro Recognizing that effective energy conservation is a key element in achieving sustainability, The Alternative Energy Company seeks to help businesses and homeowners identify and implement cost effective solutions to increase their energy efficiency and their use of renewable energy.
In a grid tied system power is generated and consumed by the owner. Excess power is returned to the local utility through the electrical grid; this power is repurchased by the utility at an avoided cost (wholesale), retail rate, or power credit depending on what the utility company offers. An agreement is put in place to spell out the safety and sell back terms for the owner and utility. This is called a Net Metering Agreement. When the alternative energy systems supplied insufficient power, the grid supplies power to the owner and charges him a retail rate or uses any credits that have been earned.
A grid tied systems consists of a solar array, an inverter (to convert DC power produced by the modules to stable 120 or 240v AC power usable by the grid and your house). The system’s inverter will shut down in the event of a loss of power. This is a safety feature so that your alternative energy system- be it solar, wind or micro-hydro- will not back feed the grid during an outage. The Net Metering Agreement is usually completed by the system’s installer. A licensed electrician will need to sign off on the Net Metering Agreement to certify the safe and correct wiring of the system.
There is little maintenance with a grid tied system.
In an off-grid system, power is generated and consumed by the owner. Excess power is used to charge batteries or in some cases fuel cells. These batteries are used to supply power when the power supplied by the alternative energy source is insufficient to supply the owner’s needs. In an off-grid system, there is an extra component called a controller. These devices insure that the batteries are not overcharged by modulating the rate of charge.
An off-grid system requires regular maintenance of the batteries to keep the system operating optimally and to improve the life of the batteries.