Categories

Systems Choose from a selection of packaged systems as a starting point for your renewable energy system!

Photovoltaic Solar Electric (photovoltaic or PV) products convert the sun's energy into electricity. This electricity is then stored in batteries for later use, used to power an appliance such as a water pump directly or fed into the power distribution grid (grid-intertie systems). This energy is then used to run lights, stereos, and any electrical appliance, although it is not generally efficient to run appliances the generate heat such as a baseboard heater or electric stove in all but the largest systems. Photovoltaics are the simplest form of alternative energy. There are no moving parts in photovoltaic modules and little maintenance is required.

Wind

Microhydro If your site has a source of running water, you simply must investigate its potential as a source of electricity. Our experience has demonstrated that water power will produce between 10 and 100 times more power than solar or wind for the same capital investment. Since water flows day and night, a microhydro system requires far less battery storage than other technologies. Even if the stream is far away, it may still be viable. Seasonal streams offer great performance when a hybrid water and solar system is designed. When your power requirements are the highest - in the winter - the water is usually flowing the fastest. Solar modules are most efficient when there is the most sun in the summer. Electricity is produced from the energy in water flowing from a high level to a lower level. This change in elevation is called “head” and supplies the pressure which drives the turbine. “Flow” is the other factor contributing to power production. It is usually limited by the size of the creek. The amount of electricity produced is directly related to the head and flow. If the head or flow is increased the power output increases proportionally.

Batteries Batteries are the heart of an independent power system. They store electricity for use at a later time when a charging source is not available. They also provide a reserve of available energy to run loads that require more power than that provided by the renewable energy source. Batteries wear out and must eventually be replaced. Regular monitoring and maintenance will extend the life of your battery and save you money. How you use and maintain your battery bank will have a direct relationship to their lifespan. The deeper you discharge these batteries, the shorter their lifespan will be. A battery bank that is too small will tend to be discharged deeper. Your battery bank is a long-term investment. Consider how you might want to expand the system in the future.

Battery Chargers Battery chargers are used to charge batteries from an external AC electricity source - typically a generator. Some sites may use shore power or grid power. Many inverters have built-in battery chargers which are generally the best value. If you are shopping for a new inverter and require battery charging as well you should consider buying an inverter with that function built in. External chargers are used for systems that do not have battery charging built on, or require additional charging power. If you have a large battery bank and a large generator, you may find you can make use of additional battery chargers, reducing the running time of your generator.

Inverters Inverters are a basic component of any independent power system that requires AC power. An inverter converts DC power stored in batteries into AC power used to run conventional appliances like computers, fridges, power tools and entertainment systems. Inverters differ in the quality of electricity they produce. Quality can vary in waveform, frequency and voltage. The type of appliance that can run off an inverter depends on the quality of electricity converted. Jargon Waveform: Represents how AC electricity varies with time. Frequency: Number of complete cycles per second of an AC current. Standard unit is Hertz (Hz). Harmonics: Varying frequencies within one wave cycle. The more harmonics, the worse the quality of the electricity. Rated power: The maximum power output of an inverter.

Generators Most year-round renewable energy systems make use of a generator to provide the extra power required. There are many choices for generators - gas, propane or diesel? Portable or stationary? Size? There are pros and cons for various types of generators

Balance of Systems

Pumps

Books and Education Looking for more information on renewable energy? Look at our selection of books and videos