Frequently Asked Questions

Solar / Wind

Q. What does the terminology mean?

Amperes measure electrical current.
Volts measure electrical pressure.
Watts measure electrical power (amperes x volts).
A kilowatt (kW) is one thousand watts.
A megawatt (MW) is one million watts or one thousand kWs.
A gigawatt (GW) is one billion watts or one thousand MWs.

Q. What is PV & how does it work?
A. PV stands for photovoltaic. A solar cell converts light to electricity. A solar cell is made of silicon, one of the most abundant elements on Earth. Computer chips are made of this same material. Basically, when light strikes the surface of a solar cell some of it is absorbed into the silicon. This light energy bumps the electrons loose and causes energy to flow. By packaging approximately 36 solar cells together a solar panel or a solar module is created. When you have more then one solar panels you create a solar array.

Q. What system type do I need?
A. Depending on you needs you can choose a stand-alone system, grid-connected system or the grid-connected system with backup capability.
A stand-alone photovoltaic system is entirely self-contained and normally includes batteries and a generator. This system is ideal for the person who lives more than an eighth of a mile from the power pole.
A grid-connected system (also know as net metering) is directly connected with the utility grid and allows the power produced by solar system to offset the amount of power purchased from the utility company.
A grid-connected system with battery and /or generator backup insures uninterrupted power if the weather is not cooperating or there is a utility power outage.

Q. How long will a solar panel last?
A. Our manufacturers warranty their solar panels for 20-25 years.

Q. How much does a system cost?
A. There are too many variables to give a simple answer. System type, size and cost are directly related to the number of appliances used and the length of time they are used. The most cost-effective first step is to make an energy assessment of your appliances and replace them with newer energy-efficient ones. It is also recommended that you switch to compact fluorescent light bulbs. The more energy you conserve, the less expensive your system will be.

Q. Can I start small and add on later?
A. Yes. If you start with a some good basic components it is easy to add to your system later. The eventual size of your system will be determined by the size and type of the inverter. With the help of a system designer you can plan your purchases to reach your ultimate goal.

Q. Can I sell power back to the utility grid?
A. What is Net Metering? Sierra Pacific Power Company has a Net Metering Program. A special meter is installed by the utility company to keep track of the power generated by the PV system as well as the power used by the home. Periodically, those amounts will be "netted" out and the homeowners will pay Sierra Pacific only for the net amount of power they used during that period. This system can be set up with or without backup capabilities. With batteries and an upgraded inverter, your home can have power even when the utility is down.

Q. Do I have to have the solar panels on my roof?
A. No. Panels can be mounted on a south-facing roof, but many people choose a ground-mount or a tracker. Trackers can be adjusted manually or automatically.

Q. Can a Homeowners Association restrict my use of solar product?
A. In Nevada there is a state law prohibiting the restriction of solar energy products in any way.

Q. Inverters? What are they and what do they do?
A. An inverter changes DC power that is stored in your batteries into standard alternating current (AC). The true sine wave inverter produces cleaner energy than which is provided by the local utility company.

Q. Will the system work on gray, cloudy or overcast days?
A. Yes, because photovoltaic energy ( "PV" or "solar power") uses the full spectrum of light, the ultraviolet rays are still charging the system, though at a reduced rate, even when the sunlight isn't visible.

Q. How can solar power work at night?
A. At night, a PV solar system draws on the power that was generated during the day and stored in the battery bank.

FAQ - Wind Turbines

Q. How do residential wind turbines work?
A. A wind turbine is installed on top of a tall tower and collects kinetic energy from the wind and converts it to electricity. This electricity is stored in batteries and is then passed through an inverter producing standard electrical power compatible with your home's electrical system.

Q. Will a small wind turbine save me money?
A. The wind turbine typically lowers your electricity bill by 50- to 90-percent. It is not uncommon for wind turbine owners with total-electric homes to have monthly utility bills of only $8 to $15 for nine months of the year. However, the economics of a wind system are very sensitive to the average wind speed in the area, and to a lesser extent, the cost of purchasing electricity. As a general rule of thumb, if economics are a concern, a turbine owner should have at least a 10-mph average wind speed and be paying at least 10 cents/kWh for electricity.

Q. What size turbine would I need for my home?
A. Homes use approximately 9,400 kilowatt-hours (kWh) of electricity per year (about 780 kWh per month). Depending upon the average wind speed in the area, a wind turbine rated in the range of 5 to 15 kilowatts would be required to make a significant contribution to meet this demand.

Q. Who should consider buying a wind turbine?
A. A residential wind turbine can be a relatively large device and is not suitable for urban or small-lot suburban homes. Except for very small wind turbines (i.e., with rotors one meter or less in diameter) on very small towers, a property size of one acre or more is desirable.

Q. How reliable are wind turbines?
A. Most small turbines have very few moving parts and do not require any regular maintenance. They are designed for a long life (up to 20 years) and operate completely automatically.

Q. How do I know if I have enough wind?
A. For most residential systems, the cost of taking wind measurements is not justified. Wind resource data published by the U.S. Department of Energy is sufficient for an experienced evaluator to predict wind turbine performance. In very hilly or mountainous areas, however, it may be best to collect wind data before purchasing a system to ensure that your site is not in a sheltered area. A system designer can help determine if your site is suitable for a wind turbine.

Q. Do wind turbines make noise or interfere with TV reception?
A. Small wind turbines do make some noise, but not enough to be found objectionable by most people. A typical residential wind system makes less noise than the average washing machine. Wind turbines do not interfere with TV reception.

Q. Will my utility allow me to hook up a wind generator?
A. Federal regulations (specifically, the Public Utility Regulatory Policies Act of 1978, or PURPA) require utilities to connect with and purchase power from small (less than 80 MW) wind energy systems. A wind turbine dealer can help you arrange the required utility company approvals.

Q. What about towers?
A. An 80- to 120-foot tower is usually supplied along with the wind turbine. Towers this tall are necessary to raise the wind turbine above turbulence generated by obstacles on the ground and trees. Wind velocity- and therefore wind turbine performance - increases with altitude. Several different types of towers are available, depending upon which manufacturer you select. Each type has its advantages; the most economical type of tower is the guyed-lattice tower, but a hinged tower may be easier for you to install yourself and provides easier access for maintenance.