No. Solar cells just convert sunlight into an electric current that must be used immediately or stored in batteries to be used later. The Hybrid system takes advantage of the high efficiency of energy production of the On Grid system, but has a limited load demand battery storage bank to supply power to critical loads in the home like certain lights or a refrigerator. Normally these critical loads do not include the air conditioning unit.

Hybrid systems are designed to supply critical loads without the benefit of a solar charge cycle period, referred to as the days of autonomy (3 days is typical). The autonomy period is based on the load demand of the appliances to be operated and the length of time those appliances are to be in operation. Of course the system can be built large enough to power any device as long as cost is not a consideration.

If a generator is available to provide recharging of the battery bank, then the days of autonomy can be shortened, as the generator would be called on to offset the loss of access to the sun's power during extended cloudy periods.

A PV array is an interconnected system of PV modules that function as a single electricity-producing unit. The modules are assembled as a discrete structure, with common support or mounting. In smaller systems, an array can consist of a single module. A complete set of components for converting sunlight into electricity includes a module, a support structure, wiring, an inverter, a meter and other equipment. In general, these systems are best for applications in which backup power must be instantly available without interruption (for example, to power computers). These systems are also good for areas where power outages are a frequent occurrence, or an area where blackouts and brownouts are relatively common such as after a hurricane.

A PV system is made up of different components. These include PV modules (groups of PV cells), which are commonly called PV panels, batteries and a charge regulator or controller for a stand-alone system, an inverter for a utility-grid-connected system and when alternating current (ac) rather than direct current (dc) is required; wiring; and mounting hardware or a framework. Systems that are connected directly to your home (98% of all systems installed do not require batteries). Hybrid systems typically require a larger up-front investment than grid-tie systems. Batteries are an additional expense, require maintenance, only last 5-10 years, decrease system efficiency and result in a more complicated system.

Many of our customers opt for a grid-tie system and purchase a standby generator with a properly installed manual transfer switch. For a given level of power output, generators are usually the least expensive option for backup power production. Generators provide the most reliable and cost effective source of extended backup power, eliminate the additional expenses related to batteries, and have backup power available for as long as they have fuel.

There are two main types of solar energy technologies:

• Photovoltaic (PV) systems, which convert sunlight directly to electricity by means of PV cells made of semiconductor materials.
• 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."

The simplest solution is to install a relatively inexpensive generator in conjunction with a manual transfer switch. The transfer switch directs the source of power for critical loads from the utility (which is presumably down) to the generator - without back-feeding the electric grid. During a power outage the transfer switch is operated and the generator is started, thereby providing power to the critical loads in the house. Total costs for this type of installation are typically in the $3,000 to $7,000 range, with manual start gasoline generators at the lower end and auto-start propane/NG generators at the higher end.

More durable diesel powered generators, such as a 10,000 watt auto-start unit, can be purchased for about $10,000. This generator has higher quality power output, requires less maintenance, and has a much longer life. Since they don't require complicated carburetion, propane/NG generators are also good solutions for remote backup systems. With these higher price range generators one can install an automatic transfer switch and auto-start capabilities so that the generator automatically begins to supply your electrical loads in the event of a power outage. Note that, with most generator systems it will take several minutes for the generator to come online and provide adequate power.

PV can be used to power your entire home or business electrical systems, including lights, cooling systems, and appliances. PV systems today can be blended easily into both traditional and nontraditional homes. The most common practice is to mount modules onto a south-facing roof or wall. For an additional aesthetic appeal, some modules resemble traditional roof shingles or can be built right into glass skylights and walls. This building-integrated PV provides a dual-use building material, reduces PV system costs by using the building as the mounting or support structure, and reduces utility bills with on-site power production. A battery based system is made up of several different components. These include solar panels, batteries and a charge regulator or controller, an inverter which converts the DC current to AC current; wiring; and mounting hardware or a framework.

Although a small amount of energy is lost in converting DC to AC (typical inverter efficiencies are in the range of 90 to 95%), an inverter makes solar generated electricity behave like utility power to operate everyday AC appliances, lights, and electrical equipment. Please note that you will need a special type of inverter if you want a battery backup system. For safety reasons most grid-tied inverters are designed to shut down completely if there is a power failure.

The charge controller prevents the solar panel or array from overcharging your battery.

Batteries are the energy storage for your system. Without batteries there is no way to store the energy your solar panels produce during the day and provide you with the energy you need at night. Typically loads receive their power from batteries instead of directly from the output of a solar panel.

The solar panel is the basic building block of the system. This is your battery charger. If you have several solar panels wired together you have created a solar array. The size of the solar array determines the amount of power or energy that will be produced.

This is a difficult question to answer. Due to the rising electrical rates the answer is not the same for everyone. Yes. A solar system on your home will lower your electric bill. If you look at the cost per kilowatt hour for a solar system over its life it can be as low as $0.06 per kilowatt hour." The batteries used in solar systems are similar to car batteries, but are designed for deep cycling use in which a larger percentage of the capacity of the battery is used each night (and then fully charged up each day). Batteries designed for solar projects pose the same risks and demand the same caution in handling and storage as automotive batteries. The fluid in unsealed batteries is highly corrosive, levels should be checked periodically, batteries must be appropriately ventilated, and batteries should be protected from extremely cold weather. In practice we have found that when properly maintained batteries last for about 5-8 years, after which their capacity is significantly diminished.

People decide to buy solar energy systems for a variety of reasons. For example, some individuals buy solar products to preserve the Earth's finite fossil-fuel resources and to reduce air pollution. Others would rather spend their money on an energy-producing improvement to their property than send their money to a utility. Some people like the security of reducing the amount of electricity they buy from their utility, because it makes them less vulnerable to future increases in the price of electricity. If it's designed correctly, a solar system might be able to provide power during a utility power outage, thereby adding power reliability to your home. Finally, some individuals live in areas where the cost of extending power lines to their home is more expensive than buying a solar energy system." The battery can be as simple as a 12 volt battery of moderate size, much like a car battery. The capacity, or the energy storage capacity, of the battery is directly related to its physical size. The larger the battery, the higher the capacity. A 7 Ampere Hour (AH) battery might be the size of an envelope box where as a 220 AH battery would be larger than a car battery. The battery bank is made up of several batteries connected together in series and parallel combinations to develop the voltage and current capacities needed for a particular system.

Two 12 volt batteries connected in series make up a 24 volt battery. This battery would have the same current capacity of either of the two batteries individually. If the 12 volt battery were to be rated for 12 volts at 220 AH then the series connected battery combination would be rated at 24 volts at 220 Ampere Hours. If we carry this out further, making a 48 volt battery by connecting the original two batteries in series with two more batteries in series (a total of 4 batteries) we make one 48 volt battery with a capacity rating of 220 AH.

Once the battery voltage is satisfied, by connecting batteries in series, we then consider the total battery Ampere Hour capacity needed. To meet this requirement we connect the 4 series connected batteries in parallel with 4 more series connected batteries, making a 48 volt battery with 440 AH capacity. And the process continues until the battery is sized to meet the load demand.

CAUTION - even a single cell battery at modest AH ratings has the ability to supply very high currents for short durations. Shorting the terminals of a battery will cause maximum current to flow, and the power will be dissipated in the load. Resistance is the limiting factor in the power transfer process. Without resistance, as in the case of a short circuit, maximum current flows for the duration of the batteries ability to contain the power developed during energy transfer process. This is limited by the physical construction of the battery and the duration of the short circuit. The battery can, and most likely will explode causing the contents of the battery, to be sent i

Net metering is a policy that allows homeowners to receive the full retail value for the electricity that their solar energy system produces. The term net metering refers to the method of accounting for the photovoltaic (PV) system's electricity production. Net metering allows homeowners with PV systems to use any excess electricity they produce to offset their electric bill. As the homeowner's PV system produces electricity, the kilowatts are first used for any electric appliances in the home. If the PV system produces more electricity than the homeowner needs, the extra kilowatts are fed into the utility grid. The real question is can I sell power back to the utility company. Most states have net metering bills that basically say the utility company will have to buy the power back from you at the same rate you buy power from them. The states that don't have net metering bills typically only pay the wholesale cost of the power about 1-3 cents. Until uniform codes have been adopted by all utilities it is best that you first check with your utility. Each utility has different interconnection standards that have to be meet before they will allow you to sell power back to the utility grid." During the charge cycle hydrogen is produced in the process, different types of batteries handle the gassing process differently, each process can be directly related to battery cost. The standard wet cell, commonly related to the car battery, just vents the gas into the air, normally the quantity is such that the concentration is not explosive. Sealed batteries will vent, but normally the gasses are contained, depending on the charge rate. In all cases one would want to consider a separated space for the batteries, certainly not within the living space.

Ideally, storage batteries would be placed in cool, dry and vented locations (batteries release hydrogen gas). Sheds or garages are good places. The contents of batteries should not be subjected to boiling or freezing. Freezing will only occur when the batteries are in a state of discharge.

The amount of solar you need to power your home is not dependent on the size of your home. The amount of solar depends on the amount of power you use in your home. Look at your monthly bill from the utility company. It will list the total amount of power (kWh) you used in the last billing cycle. Divide this by the number of days in your last billing cycle. This will tell you how much power you use each day (kWh)." Different geographic regions provide various amounts of daily sunshine. It is recommended that an off grid system has enough battery power to account for five days of inclement weather. The American southwest averages 5 sunshine hours per day and the northeast receives about 3 hours of daily sunshine. More solar panels will increase the amount of power generated when the sun is shining.

A solar generating system with batteries supplies electricity when it is needed. The amount of electricity that can be used after sunset or on cloudy days is determined by the output of the solar energy modules and the storage capacity of the battery bank. Including more modules and batteries increases system cost, so energy requirements (both in terms of peak loads and the average duration of the loads) are carefully studied to determine optimum system size. A well-designed system balances cost and convenience to meet the needs of the particular application, and can be expanded if those needs change.

It depends. The break-even point for a system depends on financing and incentives, which vary from place to place, and it depends on your solar resources and what you would pay for another source of energy. A system designer that has information about your location, the amount of energy you typically use, how much land or roof area you have for the system, etc., could give you a more accurate answer. The number of solar panels required is directly proportional to the daily power required to supply the home. Because the available energy to be harvested from the sun is calculated based on the daily average of available solar energy, the energy production per square foot of solar panel surface for that harvest must be known. If we require more solar energy to be harvested then the solar panel surface area is enlarged by the addition of more panels within the system.

Typically, a solar panel that produces at 175 watts per hour represents about 14 square feet (1.3 m2) of solar panel surface area. A 100% efficient solar would convert the standard 1,000 Watts/m2 that strikes the surface of the earth into 1300 watts of solar energy. However, at 13.46% (typical efficiency for today's solar panel technology) the same panel produces the manufacture's rating of 175 watts. A 200 watt panel of the same quality is just physically larger (more surface area).

Two 87.5 watt rated panels (physically smaller), would produce 175 watts under the same conditions. As a result the total number of solar panels needed is a ratio of available solar energy, and the daily power consumed by the system loads. If this ratio is not properly calculated, including the DC to AC conversion process and system losses, the solar panels will fail to supply the batteries with the energy required to replace what is consumed by the loads on a daily basis.

The number of panels required depends on the energy harvest required to meet the needs of the system design.

A PV system that is designed, installed, and maintained well will operate for more than 40 years. The best way to ensure and extend the life and effectiveness of your PV system is by having it installed and maintained properly. Each piece of equipment or appliance in the home (draws) a specific amount of power expressed in Watts. Watts = the applied voltage expressed as E, times the current expressed as I, passing through the device (W= E x I or Watts= Volts x Amps for this example). While in operation this power is basically supplied by the systems batteries and the solar panel array which is sized to recharge or replace the energy drawn from the batteries during the normal periods of sunlight.

Power is related to the current capacity of the batteries (expressed in Ampere Hours or AH) and determines the length of time the energy can be drawn from the battery at a rate to allow normal operation of the loads attached. The amount of energy consumed during the daily period must be put back into the batteries, or the batteries will eventually discharge below a usable level causing the system to fail.

A 100 watt lamp consumes power at a rate of 100 watts per hour for the period of time it is on. If the lamp is on for 1 hour it consumes 100 watt hours. In order to make the power available later to turn on the lamp we must recharge that 100 watt hours back into the batteries plus about 12% (112 watts) for applicable system losses.

The lamp consumes 100 watts at 120 volts so while the lamp is on the current required is relatively small (100W/120V = 0.83 amps). The power that comes from a battery is at a lower voltage, in this test case at 24 volts. Therefore, the current flowing from the battery for the period of time the lamp was on would be 4.67 amps (112W/ 24V = 4.67 amps).

In Houston we have 4.8 hours (annual average) of peak solar energy production to replace the power consumed by the lamp back into the battery. Therefore to size the solar panels required to charge the batteries at a rate to reflect the available hours of solar production is 112 watts / 4.8 hours = 23 watts/hour. So one 24 volt solar panel (typical panel voltage) rated at 28 watts can be used to keep the battery charged.

Of course that battery capacity must capable of supplying the power needed based on the total time that the devices are being used, and at the power supply rate to match the energy that is pulled out of the battery. With larger loads, like a window AC unit, more current is needed at a higher rate of power supply. This then requires a larger battery storage system.

The inverter (converts the battery power from DC to standard AC power) also needs to be sized to meet the load demand, not only the constant load, such as a light, but also the surge load caused when starting motors such as those used in an air conditioner fan and refrigerator compressors. It takes about 3 to 7 times as much energy to start the motors as it takes to operate them. For instance a 5000 BTU WINDOW AC unit requires 1,465 watts to operate but it may require 4,395 watts for a short duration to start.

A 10% efficient PV system in most areas of the United States will generate about 180 kilowatt-hours per square meter. A PV system rated at 1 kilowatt will produce about 1800 kilowatt-hours a year. To begin the design process you must list all items you are considering to power using your battery backed system by the item name, the power rating of the device, and the length of time (hours) during the week the item will be in operation. The power consumption information can be found on the manufactures tag in the same locations as the model and serial number. The power consumption may be listed as watts or the amount of current draw in amps. Most appliances require 120 volts and some requires 240 volts (110 & 120 volts are considered to be the same in this instance as are 220 & 240 volts).

A solar powered attic vent is an attic ventilation fan, which runs solely off solar power. These ventilators fall into the category of active (powered) ventilation, where outside air is forced through the attic and out the vent to effectively cool the attic space. This method of attic ventilation is many times more effective than passive (natural) ventilation since the air inside the attic is exchanged more times per an hour with a powered vent than with a passive vent.

During the warmer months, as the sun radiates heat onto your roof, your roof's shingles or tile becomes very hot. This heat is transferred through the roof and in turn heats up the air inside your attic. If the hot air stays inside your attic, the heat from this air will eventually enter your home.

While attic insulation slows this process, it does not eliminate the heat transfer process entirely. If your attic is not very well insulated, it will do very little to stop the heat from getting through. By removing the hot air from your attic, the process of heat transfer into your home is minimized. The less attic heat that is transferred into your home, the less your air conditioner will need to work. If your air conditioner unit doesn't need to run as much to keep your home cool, you save energy and money.

How much money will you save is greatly dependent on the price of the electricity in your area, the amount of attic space in your home, the efficiency of your attic insulation, and the amount of ventilation your solar attic vent is able to provide. In our experience, a typical installation will pay for itself in savings within 1-2 summers.

Ridge vents, gable vents, and dormer vents work by passive (natural) draft air convection. This means that as hot air rises in your attic, it should flow out from these vents creating a natural draft through the attic. However, as you have probably noticed if you currently have any of these vents installed in your home, they are not very effective at reducing the temperature of your attic. Turbine vents are designed to pull hot air out of your attic when the wind blows. These vents are equally ineffective at removing attic heat due to frequent mechanical problems, low air moving capability, and a dependence on the wind to supply the power needed to induce a draft through the attic.

Attic Breeze solar attic vents operate on the principle of active (forced) draft air convection. Our vents create an air draft through your attic many times more powerful than that of natural draft air convection techniques. By inducing a greater air draft through the attic, our solar attic vents can effectively cool you're your entire attic and keep it cool throughout the day.

Ridge vents do not interfere with the operation of our solar attic vents. The ridge vents work in reverse, acting as air inlet vents when your solar attic vent is in operation. Keep this in mind when deciding on the placement of your solar attic vent. When installing our products in conjunction with ridge vents, the solar attic vent unit will need to be placed lower than normal from the ridge line of the roof to appropriately balance the air flow through the attic.

Our products can be used to either replace turbine vents or work in conjunction with existing turbine vents. If replacing a turbine vent with one of our products, you will need to make the current turbine vent roof hole slightly larger to accommodate our vent. It is also good practice to restrict the air flow from any turbine or dormer vent within 10 feet of our solar attic fans to better balance total air flow through the attic. This can easily be done by tacking flashing, plywood, or even heavy cardboard to the bottom side of the passive vent. This does not need to be a permanent seal; it only needs to be a restriction to air flow.

No, not at all. You can barely hear them running when you are standing right next to one. The fan blades used in the Attic Breeze solar powered attic vents are specially designed for whisper quiet operation.

Yes, there are some applications where a solar attic vent (or any type of active attic ventilator) would not be appropriate. Attic Breeze does not recommend using our products on homes that have drop ceilings, open attic chases, or any other building feature that allows air from the living space to freely enter the attic space.

Due to our unique design, our vents pull a powerful air draft through the attic. We strongly recommend capping our sealing any open vents, chases, or ceiling seams before installing our products to minimize the potential for conditioned air seepage into the attic space.

If properly installed, the answer is no. Any powered attic fan (including ours) needs the required amount of air intake vents to operate properly. If the necessary amount of air intake vents are available, then air flow through the attic will follow the path of least resistance and depressurization of the attic will not be possible.

No, our solar attic vents ship completely assembled and ready for use. All you need to do is install the unit.

Attic Breeze solar attic vents include a thermal switch as part of our standard package. When your attic temperature is less than about 80°F-90°F, the thermal sensor will shut down the attic fan. We do this for the following reasons: "1. During the fall and spring when attic temperatures are less than 90°F, there is very little driving force for heat transfer across the insulation in your attic (20°F temperature difference between the attic and living area vs. 70°F difference during the summer when the attic is hot). 2. By shutting down the attic fan when it is not needed, we can greatly extend the run life of the fan motor. 3. Additionally, in many areas of the country where attic moisture build up during winter is not an issue, shutting down the attic fan will help reduce winter heating bills (heat can flow in either direction through your attic insulation; the greater the temperature difference between the attic and living area, the greater the amount of heat transfer regardless of how much insulation is present).

Yes, this is an option you can choose during purchasing.

No, a battery isn't necessary. Our attic vents run when the sun is out to keep your attic cool. If our vents are doing their job properly, your attic will not be hot when the sun goes down and shouldn't need any additional night time cooling. Likewise, if the sun isn't out due to rain or cloud cover, then your attic isn't getting hot and doesn't need cooling.

Our attic vents are built entirely from high quality, corrosion resistant metal alloy parts and are designed to withstand tough weather conditions.