What is the energy payback for photovoltaics? Producing electricity with solar photovoltaics (PV) emits no pollution, produces no greenhouse gases, and uses no finite fossil-fuel resources. The environmental benefits of PV are great. But just as we say that it takes money to make money, it also takes energy to save energy. The term “energy […]
LED technology continues to develop rapidly as a general light source. As more LED lighting products are introduced on the market, what do retailers, energy efficiency advocates, and consumers need to know to make informed buying decisions? Are LEDs ready for general consumer use? The number of white-light LED products available on the market continues […]
Part 5 of Geothermal Energy Under Our Feet. Today’s U.S. geothermal industry is a $2-billion per-year enterprise involving over 2800 MW of electricity generation capacity, about 620 MW of thermal energy capacity in direct-use applications such as indoor heating, greenhouses, food drying, and aquaculture, and over 7,300 MW of thermal energy capacity from geothermal heat […]
Part 4 of Geothermal Energy Under Our Feet. Hydrothermal A hydrothermal system is defined as a subterranean geothermal reservoir that transfers heat energy upward by vertical circulation of fluids driven by differences in fluid density that correspond to differences in temperature (see Figure 2). Hydrothermal systems can be classified into two types—vapor-dominated and hot water— […]
Part 4 of United States Climate Change Impact. Carbon dioxide concentration has increased due to the use of fossil fuels in electricity generation, transportation, and industrial and household uses. It is also produced as a by-product during the manufacturing of cement. Deforestation provides a source of carbon dioxide and reduces its uptake by trees and […]
Part 5 of Geothermal Energy: Power from the Depths of the Earth. The geothermal heat pump doesn’t create electricity—but it greatly reduces consumption of it. If you would like to reduce the cost of heating and cooling your home, you might want to consider installing a geothermal heat pump, an economical and energy-efficient technology for […]
Part 3 of Geothermal Energy: Power from the Depths of the Earth. Flip a switch and light up a room—what could be easier? Push a button on the TV remote control and be entertained. It all seems so simple that we are often unaware of the true environmental and social cost of these conveniences—and who […]
Part 2 of Geothermal Energy: Power from the Depths of the Earth. Geothermal energy delivers some powerful environmental and economic benefits. If you live in an area that uses geothermal resources for electricity production, you’re quite fortunate. Consider Lake County, California, which is home to many of the geothermal power plants at our nation’s best-developed […]
Part 1 of Geothermal Energy: Power from the Depths of the Earth. The Earth’s crust is a bountiful source of energy—and fossil fuels are only part of the story. Heat or thermal energy is by far the more abundant resource. To put it in perspective, the thermal energy in the uppermost six miles of the […]
Part 2 of Small Hydropower Systems. Of course to build a small hydropower system, you need access to flowing water. A sufficient quantity of falling water must be available, which usually, but not always, means that hilly or mountainous sites are best. Next you’ll want to determine the amount of power that you can obtain […]
Part 1 of Small Hydropower Systems. If you’re considering building a small hydropower system on water flowing through your property, you have a long tradition from which to draw your inspiration. Two thousand years ago, the Greeks learned to harness the power of running water to turn the massive wheels that rotated the shafts of […]
Energy vampires are sitting in dark corners, hiding under desks, and lurking on counter tops in offices across America. They take the form of office equipment, personal electronics, and appliances that draw electricity when left in “standby mode.” These sneaky monsters continue to consume power, even when equipment is idle or “shut off.” While you […]
The easiest way to size your solar electric system is to have a vendor come to your home and perform a site analysis and load assessment. Solar electric vendors have the experience and tools necessary to gather the data needed for the calculations. Most vendors will supply predesigned package systems that range from one kilowatt […]
The winter months bring snow and ice storms, power outages and hazardous driving conditions. However, you can prepare for a disaster by taking a few steps to deal with the challenges of winter weather. Compile an emergency survival kit that includes a three day supply of food and water, flashlights, a first aid kit, a […]
Most of us are aware that windows provide us with natural light, ventilation, and a view. But windows still remain the least understood building design component, even though many homeowners place much importance on the functioning and energy efficiency of their windows. Windows transmit not only sunlight but also both indoor heat and solar heat […]
Part 15 of Buying and Using Renewable Energy at Home. One of the more challenging ways to use clean energy is in fueling our cars. Advanced transportation technologies—including fuel cells, electric motors, advanced engines, improved materials, and other technologies—aim to reduce pollution and minimize petroleum fuel use in cars, trucks, buses, fleet vehicles, and public […]
Part 13 of Buying and Using Renewable Energy at Home. One of the most energy-efficient options for heating and cooling your home draws on another form of renewable energy—geothermal energy, or heat from the earth. This is not the hot steam and heat that comes from deep underground (discussed here). Rather, geothermal heat pumps draw […]
Part 11 of Buying and Using Renewable Energy at Home. Your dealer can help you analyze your loads and size your system correctly. The dealer will install your equipment, making sure that it runs properly. Dealers will also have contacts at the local utility if you are connecting your system to the utility grid. With […]
Part 10 of Buying and Using Renewable Energy at Home. In addition to wind turbines, PV modules, or a microhydropower generator, you must purchase BOS equipment, when generating your own power. This may include battery charge controllers, batteries, inverters, wires, conduit, a grounding circuit, fuses, safety disconnects, outlets, metal structures for supporting the PV modules, […]
Part 9 of Buying and Using Renewable Energy at Home. According to many renewable energy experts, a standalone “hybrid” system that combines generation sources, such as wind and PV, offers several advantages over a single generation system. In much of the United States, wind speeds are low in the summer when the sun shines brightest […]
Part 7 of Buying and Using Renewable Energy at Home. Photovoltaic cells produce direct current (DC) electricity. About 40 cells are joined together in enclosed, protective casings called modules. About ten of these modules are mounted in one PV panel. These flatplate PV panels can be mounted facing south, or they can be mounted on […]
Part 6 of Buying and Using Renewable Energy at Home. All wind energy systems consist of a wind turbine, a tower, wiring, and the “balance of system” (BOS) components: controllers, inverters, and/or batteries. Home wind turbines consist of a rotor, a generator mounted on a frame, and (usually) a tail. With the spinning blades, the […]
Part 5 of Buying and Using Renewable Energy at Home. At first glance, generating your own electricity using renewable fuel sources seems like the ideal way to avoid monthly utility bills. For some homeowners, self-generation is a choice that makes sense for their circumstances and fits into their values. However, self-generation involves investing your money […]
Part 4 of Buying and Using Renewable Energy at Home. The following briefly describes renewable energy technologies that might be offered in green pricing programs or competitive markets in your area. If you do not currently have the option to choose your electricity supplier, contact your utility to find out what their plans are regarding […]
Part 3 of Buying and Using Renewable Energy at Home. When describing electricity production, the terms electric power (or capacity) and electric energy (or electricity) are often used. “Power” is the ability to do work and “energy” is the actual performance of the work, or the use of that ability over a period of time. […]
Just a few years ago, we did not have the ability to choose our electric service. Currently, the electricity industry is undergoing changes that will bring choice to many consumers across the country. Already, utility customers can choose to obtain electricity from clean generation sources—also known as green power. Green power is electricity that is […]
After you have assessed the appropriateness of your site, you need to determine how much electricity your PV system must generate. This depends on how much electricity your loads require. Again, your dealer can help you with sizing a system that will meet your needs. The sidebar illustrates the steps involved in sizing a PV […]
The basic types of air conditioners are room air conditioners, central air conditioners split-system, central air conditioners and packaged. Room air conditioners are installed directly in the windows or walls, which means they have no pipeline. The fan spray faces inside, while the condenser fan is facing outside. Room Air Conditioners Room fresh air conditioners rooms […]
Part 12 of Advanced Technology and Alternative Fuel Vehicles. No matter what the fuel, the higher the fuel economy of a car or truck, the less it pollutes. Fuel economy becomes even more important when you consider the growing popularity of sport utility vehicles (SUVs). According to Automotive News, General Motors expects SUVs to outsell […]
Part 9 of Advanced Technology and Alternative Fuel Vehicles. Hydrogen is a simple, abundant element found in organic matter, notably in the hydrocarbons that make up many of our fuels, such as gasoline, natural gas, methanol, and propane. As an energy carrier like electricity (not an energy source), it must be manufactured. Hydrogen can be […]
Part 8 of Advanced Technology and Alternative Fuel Vehicles. Electricity is considered a fuel when used in vehicles. Electric vehicles use various types of batteries and other energy storage mechanisms to store the electricity used to run a vehicle. While the electricity production process for vehicles may contribute somewhat to air pollution, an electric vehicle […]
Part 4 of Advanced Technology and Alternative Fuel Vehicles. Biodiesel is an ester (like vinegar) that can be manufactured from different types of oils such as vegetable oils and animal fats. Each year about 30 million litres of biodiesel is produced in the USA recycled cooking oils and soybean oil. Biodiesel is currently not available […]
Part 2 of Advanced Technology and Alternative Fuel Vehicles. Not only do alternative fuels burn cleaner to reduce emissions, but some are also renewable, unlike fossil fuels, which means that we could develop a continuous supply of them. Alternative fuels in use today include ethanol, biodiesel, methanol, natural gas, propane, electricity and hydrogen. Biofuels are […]
Part 1 of Energy-Efficient Water Heating. The next time you pay your utility bill, try one simple calculation. Divide the total amount by seven. The result is the amount you spend to heat your water. (If you receive separate utility bills for gas and electricity, use the gas bill for this calculation if you have […]
Part 3 of Battery Power for Your Residential Solar Electric System. A long cycle life, or how many deep discharges the batteries can provide. Thick lead plates—the thicker the plates, the deeper the discharge and the longer the battery life. If you have flooded batteries, look for space at the bottom of the battery case […]
Part 1 of Battery Power for Your Residential Solar Electric System. A Winning Combination—Design, Efficiency, and Solar Technology A battery bank stores electricity produced by a solar electric system. If your house is not connected to the utility grid, or if you anticipate long power outages from the grid, you will need a battery bank. […]
Part 1 of Zero Energy Community. Vista Montaña In August 2003, Clarum Homes opened the doors at Vista Montaña, California’s largest Zero Energy Home community, with homes designed to use almost zero net electricity over the course of a year. Built on a former apple orchard, all homes in the development will harvest the sun to […]
Part 14 of Get Your Power from the Sun. Connecting your photovoltaic system to the utility grid will require an interconnection agreement and a purchase and sale agreement. Federal law and some state public utility commission regulations require utilities to supply you with an interconnection agreement. Some utilities have developed simplified, standardized interconnection agreements for […]
Part 11 of Get Your Power from the Sun. If you decide to get more than one bid for the installation of your photovoltaic system (always a good idea), make sure that all bids are made on the same basis. For example, a bid for a system mounted on the ground is usually very different […]
Part 7 of Get Your Power from the Sun. No single answer applies in every case. But a solar rebate and other incentives can always reduce the cost. Your price depends on a number of factors, including whether your home is under construction and whether photovoltaic is integrated into the roof or mounted on top […]
Part 5 of Get Your Power from the Sun. Can you locate your system so it works well? A well-designed photovoltaic system needs clear and unobstructed access to the sun’s rays for most or all of the day, throughout the year. You can make an initial assessment yourself. If the location looks promising, your photovoltaic provider […]
Part 4 of Get Your Power from the Sun. People decide to buy photovoltaic systems for a variety of reasons. Some people want to help preserve the Earth’s finite fossil-fuel resources and reduce air pollution. Others want to invest in an energy-producing improvement to their property. Some people like the security of reducing the amount […]
Part 3 of Get Your Power from the Sun. Yes, many states offer incentives. For specific information, call one of the contacts listed under “Getting Help”. Another excellent source is the National Database of State Incentives for Renewable Energy (DSIRE). Prepared by the North Carolina Solar Center, this database contains information on financial and regulatory […]
Part 2 of Get Your Power from the Sun. Photovoltaic (PV) systems convert sunlight directly to electricity. They work any time the sun is shining, but more electricity is produced when the sunlight is more intense and strikes the photovoltaic modules directly (as when rays of sunlight are perpendicular to the photovoltaic modules). Unlike solar […]
Part 1 of Get Your Power from the Sun. Are you thinking about buying a solar electric system for your home or business? If so, this story provides some basic information that can help you. Solar electric systems, which are also called photovoltaic or PV systems, are reliable and pollution-free. They make use of a […]
Part 5 of Learn About Saving Energy. Coal:A solid fossil fuel found in the earth. Coal is burned to make electricity. Compact fluorescent lights (CFL) or Compact fluorecent bulbs (CFB): Lights that use a lot less energy than regular light bulbs. We can use compact fluorescent lights for reading lights and ceiling lights. Energy: Energy […]
Part 3 of Learn About Saving Energy. It is important to save energy because most of the energy we use comes from fossil fuels. If we use up all our fossil fuels, there will not be any left for people to use in the future. It would be impossible to stop using energy. But we […]
Part 1 of Learn About Saving Energy. Energy is the ability to do work. It can come in the forms of heat and light. There are two types of energy: working energy and stored energy. Stored energy becomes working energy when we use it. You eat food for energy. Then your body stores the energy […]
Part 4 of Selecting a New Water Heater. Heat pump water heaters use electricity to move heat from one place to another instead of generating heat directly. To heat water for homes, heat pump water heaters work like refrigerators in reverse. Heat pump water heaters can be purchased as integral units with built-in water storage […]
Part 2 of Selecting a New Water Heater. Storage water heaters remain the most frequently used type of water heater for residential purposes. A variety of fuel options are available for conventional storage water heaters—electricity, natural gas, oil, and propane. Ranging in size from 20 to 80 gallons (75.7 to 302.8 liters), storage water heaters […]
Part 1 of Conserve Energy and Heat Your Swimming Pool with Solar Energy. Swimming pools provide a great way to exercise and beat the summer heat. Building and maintaining a pool, however, also means relatively high costs added to your household’s budget. There are several ways that you can reduce operating and maintenance costs, lower […]
Part 9 of Ways to Save Money on Energy at Home. Appliances account for about 20% of your household’s energy consumption, with refrigerators, clothes washers, and clothes dryers at the top of the consumption list. When you’re shopping for appliances, you can think of two price tags. The first one covers the purchase price—think of […]
Part 8 of Ways to Save Money on Energy at Home. Increasing your lighting efficiency is one of the fastest ways to decrease your energy bills. If you replace 25% of your lights in high-use areas with fluorescents, you can save about 50% of your lighting energy bill. Indoor Lighting Use linear fluorescent and energy-efficient compact […]
Part 5 of Ways to Save Money on Energy at Home. Hot Water Usage (based on national averages) Shower: 37% Clothes washer: 26% Dishwasher: 14% Bath: 12% Sinks: 11% Water heating is the third largest energy expense in your home. It typically accounts for about 14% of your utility bill. There are four ways to cut […]
Part 4 of Ways to Save Money on Energy at Home. Heating and cooling your home uses more energy and drains more energy dollars than any other system in your home. Typically, 44% of your utility bill goes for heating and cooling. What’s more, heating and cooling systems in the United States together emit over a […]
Part 1 of Ways to Save Money on Energy at Home. Did you know that the typical U.S. family spends close to $2,100 (2008 dollars) a year on their home’s utility bills? Alas, a significant portion of that energy is wasted. The amount of energy wasted just through poorly insulated windows and doors is about as much […]
Part 5 of Heat Your Water With The Sun. Your savings depend on how your solar system will be used, as well as the size and type of your system. Other factors can include the climate, the contractor, and the system rating. Your state may offer solar rebates or other incentives that will reduce costs. […]
Part 3 of Heat Your Water With The Sun. Why should I invest in a solar thermal system? The first question many people ask when considering a home expense is, “How much will it cost?” The answer depends on the type of system, how you want to use it (water or pool heating, for example), […]
Part 2 of Heat Your Water With The Sun. What is solar heating? Solar heaters, or solar thermal systems, provide environmentally friendly heat for household water, space heating, and swimming pools. The systems collect the sun’s energy to heat air or a fluid. The air or fluid then transfers solar heat directly or indirectly to […]
Part 1 of A Guide to Making Energy-Smart Purchases. If you feel that energy bills are taking a big chunk of change out of your pocket, you are not alone. Americans spend more than $115 billion each year on fuel and electricity for their homes. On the average, heating and cooling (space conditioning) account for […]