A: Factors include the amount of sunlight available at the site location, local utility rates, solar incentives, air conditioning savings, roof maintenance avoidance, tax credits, improved power quality.

Q: What happens when the sun doesn't shine?
A: In remote, off-grid sites, the PV system is connected to a battery storage system. In grid-tied applications like APS, the PV system works in parallel with the utility power grid. When building load exceeds the solar electric output, the utility supplements the power. When the PV system generates more energy than the building requires, the excess is fed back to the grid. Also know as net metering.

Q: How long does a PV system last?
A: The PV systems have a 25 to 30-year design life.  PV modules carry 20-25 year power guarantees from their manufacturers.

Q: Are photovoltaics a proven technology?
A: PV is the single most reliable energy system in existence. Solar electric systems have operated without maintenance for decades, even in the hostile environment of outer space.

Q: What is “Off Grid”
A: When you generate your own electricity with solar you have a back-up source of power if the electric grid goes down.  In the event of an earthquake or other emergency situation you will generate power during the day and operate with stored electricity at night.

Q: What is grid tied?
A: When the PV system generates more energy than the building requires, the excess is fed back to the grid. Also know as net metering. Additionally, you remain connected to the power grid at all times so you draw all the power you need at night and on overcast or rainy days and build up your credit balance with your electric company when the sun shines again.

About Photovoltaic’s

Q:  What does photovoltaic (PV) mean?
A: The word 'photovoltaic' essentially means electricity from the energy of sunlight. First used in about 1890, the word has two parts: photo, derived from the Greek 'phos' meaning light, and volt, a unit of measurement named for Alessandro Volta (1745-1827), a pioneer in the study of electricity.

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Q:  How does PV differ from other solar energy technologies?
A: There are four main types of solar energy technologies:

1. Photovoltaic (PV) systems, which convert sunlight directly to electricity by means of PV cells made of semiconductor materials.
2. Concentrating solar power (CSP) systems, which concentrate the sun's energy using reflective devices such as troughs or mirror panels to produce heat that is then used to generate electricity.
3. Solar water heating systems, which contain a solar collector that faces the sun and either heats water directly or heats a 'working fluid' that, in turn, is used to heat water.
4. Transpired solar collectors, or 'solar walls', which use solar energy to preheat ventilation air for a building.

Q:  What are the components of a PV system?
A: A PV system is made up of several different components. These include groups of PV cells called 'modules' (also known as 'panels'); one or more batteries; a charge regulator or controller for a stand-alone system; an inverter for a utility-grid-connected system or when alternating current (AC) rather than direct current (DC) is required; wiring; and mounting hardware or a framework.


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Q:  Where are PV systems being used?
A: PV systems are generating clean power in a whole host of applications right across the world - from urban skyscrapers to remote villages in developing countries. PV electricity can be used to power all manner of household appliances, computing and communications equipment, water pumping and lighting. Cost-effective examples of lighting powered by PV include small garden lights, street lights, lighting for recreational areas, highway signs, warning signs and signals, and lighting for businesses and homes. Virtually any power need can be met with PV.


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Q:  When will PV systems replace coal and nuclear power plants?
A: A major driver in the deployment of solar systems is public demand for clean energy. Fossil-based energy pollutes the environment, and nuclear energy creates hazardous waste. If we stop to consider the environmental and health costs of fossil-fuel and nuclear energy, then solar energy makes sense. So, in the coming decades, we will begin to see many more solar energy systems being built in areas that now use fossil fuels and nuclear energy for electricity generation. In developing countries, where there is little or no supply system for conventional energy, solar energy is already being used because it is much less expensive than many other options, and the environmental benefits associated with this cleaner form of energy are significant.


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Q:  How much space would be needed for PV systems to meet the entire world's electricity needs?
A: Contrary to some popular notions, the landscape of a world relying on PV would be almost indistinguishable from the landscape we know today. There are three reasons for this. First, PV systems have sitting advantages over other technologies. They can be put on roofs and can even be an integral part of a building. Second, even ground-mounted PV collectors are efficient from the perspective of land use. Flat-plate PV technology is the most land-efficient means to produce renewable energy. Third, adequate sunlight is ubiquitous and often abundant, and present in predictable amounts almost everywhere. 

For example, in the United States, cities and residences cover about 140 million acres of land. The nation's energy requirements could be met simply by applying PV to 7% of this area - on roofs, on parking lots, along highway walls, on the sides of buildings, and in other dual-use scenarios. Not one single acre of new land would need to be appropriated to make PV the primary energy source.

About Photovoltaic’s

Q: What does photovoltaic (PV) mean?
A: The word 'photovoltaic' essentially means electricity from the energy of sunlight. First used in about 1890, the word has two parts: photo, derived from the Greek 'phos' meaning light, and volt, a unit of measurement named for Alessandro Volta (1745-1827), a pioneer in the study of electricity.


Top


Q: How does PV differ from other solar energy technologies?
A: There are four main types of solar energy technologies:

1. Photovoltaic (PV) systems, which convert sunlight directly to electricity by means of PV cells made of semiconductor materials.
2. Concentrating solar power (CSP) systems, which concentrate the sun's energy using reflective devices such as troughs or mirror panels to produce heat that is then used to generate electricity.
3. Solar water heating systems, which contain a solar collector that faces the sun and either heats water directly or heats a 'working fluid' that, in turn, is used to heat water.
4. Transpired solar collectors, or 'solar walls', which use solar energy to preheat ventilation air for a building.

Top


Q: What are the components of a PV system?
A: A PV system is made up of several different components. These include groups of PV cells called 'modules' (also known as 'panels'); one or more batteries; a charge regulator or controller for a stand-alone system; an inverter for a utility-grid-connected system or when alternating current (AC) rather than direct current (DC) is required; wiring; and mounting hardware or a framework.


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Q: How long do PV systems last?
A: A PV system that is well designed, installed and maintained can operate for more than 20 years. The basic PV module has no moving parts and can last more than 30 years. The best way to ensure and extend the life and effectiveness of your PV system is by having it properly installed and well maintained.


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Q: Where are PV systems being used?
A: PV systems are generating clean power in a whole host of applications right across the world - from urban skyscrapers to remote villages in developing countries. PV electricity can be used to power all manner of household appliances, computing and communications equipment, water pumping and lighting. Cost-effective examples of lighting powered by PV include small garden lights, street lights, lighting for recreational areas, highway signs, warning signs and signals, and lighting for businesses and homes. Virtually any power need can be met with PV.


Top


Q: When will PV systems replace coal and nuclear power plants?
A: A major driver in the deployment of solar systems is public demand for clean energy. Fossil-based energy pollutes the environment, and nuclear energy creates hazardous waste. If we stop to consider the environmental and health costs of fossil-fuel and nuclear energy, then solar energy makes sense. So, in the coming decades, we will begin to see many more solar energy systems being built in areas that now use fossil fuels and nuclear energy for electricity generation. In developing countries, where there is little or no supply system for conventional energy, solar energy is already being used because it is much less expensive than many other options, and the environmental benefits associated with this cleaner form of energy are significant.


Top


Q: How much space would be needed for PV systems to meet the entire world's electricity needs?
A: Contrary to some popular notions, the landscape of a world relying on PV would be almost indistinguishable from the landscape we know today. There are three reasons for this. First, PV systems have sitting advantages over other technologies. They can be put on roofs and can even be an integral part of a building. Second, even ground-mounted PV collectors are efficient from the perspective of land use. Flat-plate PV technology is the most land-efficient means to produce renewable energy. Third, adequate sunlight is ubiquitous and often abundant, and present in predictable amounts almost everywhere. 

For example, in the United States, cities and residences cover about 140 million acres of land. The nation's energy requirements could be met simply by applying PV to 7% of this area - on roofs, on parking lots, along highway walls, on the sides of buildings, and in other dual-use scenarios. Not one single acre of new land would need to be appropriated to make PV the primary energy source.


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PV and You

Q: Why should I use PV-generated electricity?
A: For a growing number of users, particularly those who are environmentally aware, PV is the clear choice. PV provides sustainable energy, operates silently, produces no toxic emissions or greenhouse gases, and causes no hazardous waste. PV systems generate electricity using the Sun's free energy, so the ongoing costs are minimal. Moreover, continued R&D means installation costs are gradually being reduced. Some people would rather invest capital on an energy-producing improvement to their property than continually send money to a power company. Others like the security of reducing the amount of electricity they buy from power utilities, because it makes them less vulnerable to power outages and future increases in the price of electricity.

Q:  How do I know if I have enough sunlight for PV?
A: A PV system needs unobstructed access to the sun's rays for most or all of the day. Climate is not really a concern because PV systems are relatively unaffected by severe weather. In fact, some PV modules actually work better in colder weather. There is enough sunlight to make solar energy systems useful and effective almost anywhere in the world. Most homes have adequate roof space for a PV system, and this can be complemented by integrating the system into walls or by using modules to cover a porch or patio in the backyard.


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Q:  How big a PV system do I need?
A: The size of solar system you need depends on several factors-such as how much electricity or hot water or space heat you use, how much sunshine is available where you are, the size of your roof, and how much you're willing to invest. A PV system does not necessarily have to cover 100% of your energy needs. In most cases a PV system is connected to the grid so that the solar electricity generated is sold to the utility company and you continue to buy electricity as normal.


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Q:  Are there disadvantages to using solar energy?
A: Solar energy technologies often have a higher initial cost outlay. This means that a person is likely to pay more money up front to purchase and install a solar system. Most systems have a breakeven point in about 7–10 years. Still, in nearly all cases, the high initial cost is recovered through substantial fuel savings, exempt from price hikes, rebates and tax incentives over the life of the product.