The sun’s heat and light provide an abundant source of energy that can be harnessed in many ways. There are a variety of technologies that have been developed to take advantage of solar energy. These include concentrating solar power systems, passive solar heating and daylighting, photovoltaic systems, solar hot water, and solar process heat and space heating and cooling. Solar power can be used in both large-scale applications and in smaller systems for the home. Businesses and industry can... 

It seems impossible that a gallon of gasoline, which weighs about 6.3 pounds, could produce 20 pounds of carbon dioxide (CO2) when burned. However, most of the weight of the CO2 doesn’t come from the gasoline itself, but the oxygen in the air. When gasoline burns, the carbon and hydrogen separate. The hydrogen combines with oxygen to form water (H2O), and carbon combines with oxygen to form carbon dioxide (CO2). How Can A Gallon of Gasoline Produce 20 Pounds of Carbon Dioxide? A carbon atom... 

A hybrid car with a series configuration uses the heat engine or fuel cell with a generator to produce electricity for the battery pack and electric motor. Series hybrid cars have no mechanical connection between the hybrid power unit and the wheels; this means that all motive power is transferred from chemical energy to mechanical energy to electrical energy, and back to mechanical energy to drive the wheels. Here are some benefits of a series configuration: The engine never idles, which reduces... 

A hybrid electric vehicle (HEV) with a parallel configuration has a direct mechanical connection between the hybrid power unit and the wheels, as in a conventional vehicle, but also has an electric motor that drives the wheels. For example, a parallel vehicle could use the power created by an internal combustion engine for highway driving while using both the engine and electric motor power for accelerating. Some benefits of a parallel configuration are: A smaller engine provides more efficient... 

An energy storage system is an essential component in hybrid cars. Batteries used in hybrid cars should have high power (with high-peak and pulse-specific power), high specific energy at pulse power, high charge acceptance to maximize regenerative braking utilization, and long calendar and cycle life. See below to learn about hybrid car battery options, ultracapacitors (another energy storage device), and battery thermal management strategies. Lead-Acid Batteries Lead-acid batteries can be designed... 

Hybrid cars provide benefits to consumers, fleets, and the nation. These advanced cars cut fuel use and costs while maintaining performance, protecting public health and the environment, and increasing U.S. energy security. Cutting Fuel Use and Costs while Maintaining Performance Hybrid cars can drive 40 to 70 miles on one gallon of gasoline, much farther than a conventional car. Hybrid cars are cost competitive with similar conventional cars. What cost premiums there are for hybrid cars can be offset... 

Electricity can be used as a transportation fuel to power battery electric vehicles. Electric cars store electricity in an energy storage device, such as a battery. The electricity powers the vehicle’s wheels via an electric motor. Electric cars have limited energy storage capacity, which must be replenished by plugging into an electrical source. What Is an Electric Vehicle? In an electric car, a battery or other energy storage device is used to store the electricity that powers the motor.... 

Low-level ethanol blends are sold in every state. In fact, nearly half of U.S. gasoline now contains up to 10% ethanol (E10) to boost octane or meet air quality requirements. The Clean Air Act Amendment of 1990 (and subsequent laws) mandated the sale of oxygenated fuels in areas with unhealthy levels of carbon monoxide. This kicked off the modern U.S. ethanol industry growth. Problems with groundwater contamination from the use of methyl tertiary butyl ether (MTBE)—the only other available... 

Fuel cell cars, powered by hydrogen, have the potential to revolutionize our transportation system. They are more efficient than conventional internal combustion engine vehicles and produce no harmful tailpipe exhaust – their only emission is water. Fuel cell vehicles and the hydrogen infrastructure to fuel them are in an early stage of development.  What is a Fuel Cell Car? Like electric cars, fuel cell cars use electricity to power motors located near the vehicle’s wheels. In contrast... 

Hydrogen can be produced from diverse domestic resources, with the potential for near-zero greenhouse gas emissions. Once produced, it generates power without exhaust emissions in fuel cells. It holds promise for economic growth in both the stationary and transportation energy sectors. Increasing Energy Security The United States imports more than 60% of its petroleum, two-thirds of which is used to fuel vehicles in the form of gasoline and diesel. The demand for petroleum imports is increasing....