Question: Where do off-grid PV systems store excess electricity?
Answer: rechargeable batteries

Question: What do off-grid PV systems use to store excess electricity?
Answer: rechargeable batteries

Question: What are the programs that gives credit to households for delivering electricity to the grid called?
Answer: Net metering programs

Question: How is the credit to households accomplished?
Answer: by 'rolling back' the meter whenever the home produces more electricity than it consumes

Question: Why is a second meter usually unnecessary to monitor electricity use?
Answer: Most standard meters accurately measure in both directions

Question: When water is released due to high demand, the pump become swhat?
Answer: a hydroelectric power generator

Question: Pumped-storage hydroelectricity stores energy in what form?
Answer: water pumped when energy is available from a lower elevation reservoir to a higher elevation one

Question: How is the energy stored by pumped-storage hydroelectricity recovered?
Answer: by releasing the water, with the pump becoming a hydroelectric power generator

Question: The oil embargo in what year was a contributing factor to the reorganization of energy policies?
Answer: 1973

Question: What brought attention to solar technologies in the 1970s?
Answer: The 1973 oil embargo and 1979 energy crisis

Question: What are the names of some of the incentive programs used to promote solar technology?
Answer: the Federal Photovoltaic Utilization Program in the US and the Sunshine Program in Japan

Question: What is the name of the solar energy research facility in the US?
Answer: SERI, now NREL

Question: What is the name of the solar energy research facility in Japan?
Answer: NEDO

Question: What is the name of the solar energy research facility in Germany?
Answer: Fraunhofer Institute for Solar Energy Systems ISE

Question: The solar water heaters introduced in the US in the 1890s saw growth until what time period?
Answer: the 1920s

Question: Since 1999, what average rate has the solar water heating sector progressed at?
Answer: 20% per year

Question: When did the use of solar water heaters in the US first begin?
Answer: in the 1890s

Question: Why did interest in solar water heating decrease in the 1980s?
Answer: falling petroleum prices

Question: Growth of solar water heating development has averaged how much per year since 1999
Answer: 20%

Question: What was the estimated capacity of solar water heating and cooling in 2007?
Answer: 154 GW

Question: Which organization believes that solar energy can solve some of our most pressing issues?
Answer: The International Energy Agency

Question: Who said that solar energy can help solve some of the most urgent problems in the world?
Answer: The International Energy Agency

Question: ISO 9050 relates to standards for what?
Answer: glass in building

Question: ISO 10217 relates to standards for what?
Answer: materials used in solar water heaters

Question: What is the name of the standard related to glass in building?
Answer: ISO 9050

Question: What is the name of the standard related to the materials used in solar water heaters?
Answer: ISO 10217

Question: What are the technologies used to capture solar energy characterized as?
Answer: passive solar or active solar

Question: What are some active solar techniques used to harness solar energy?
Answer: photovoltaic systems, concentrated solar power and solar water heating

Question: What is an example of a passive solar technique?
Answer: orienting a building to the Sun

Question: What was the total worldwide energy consumption in 2012?
Answer: 559.8 EJ

Question: What is solar energy's yearly potential?
Answer: 1,575–49,837 exajoules (EJ)

Question: What makes solar energy an appealing source of electricity>
Answer: The large magnitude of solar energy available

Question: Who estimated the annual potential of solar energy in 2000?
Answer: The United Nations Development Programme

Question: How will solar energy increase energy security?
Answer: through reliance on an indigenous, inexhaustible and mostly import-independent resource

Question: What costs will solar energy lower?
Answer: the costs of mitigating global warming

Question: What should the cost of incentives for producing solar energy be considered?
Answer: learning investments

Question: What effect will solar energy have on the price of fossil fuels?
Answer: keep fossil fuel prices lower than otherwise

Question: Why does the amount of usable solar energy differ from the amount near the planets surface?
Answer: geography, time variation, cloud cover, and the land available to humans

Question: Why does geography have an effect of the amount of solar energy available?
Answer: areas that are closer to the equator have a greater amount of solar radiation

Question: What is the process called that can increase solar energy in areas further away from the earth's equator?
Answer: photovoltaics

Question: Why does time have an effect of the amount of available solar energy?
Answer: during the nighttime there is little solar radiation on the surface of the Earth for solar panels to absorb

Question: What effect does cloud coverage have on the amount of solar energy available?
Answer: clouds block incoming light from the sun and reduce the light available for solar cells

Question: Why does land availability have an effect on solar energy?
Answer: solar panels can only be set up on land that is unowned and suitable for solar panels

Question: Why are roofs a good place for solar panels?
Answer: many people have discovered that they can collect energy directly from their homes this way

Question: What factors were taken into account in the estimate published in 2000 on solar energy?
Answer: insolation, cloud cover, and the land that is usable by humans

Question: What was the total potential of solar energy found in the estimate?
Answer: 1,575–49,837 EJ per year

Question: What is solar power?
Answer: conversion of sunlight into electricity

Question: How is sunlight converted into electricity?
Answer: either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP)

Question: What does a concentrated solar power system use?
Answer: lenses or mirrors and tracking systems

Question: What is the purpose of a concentrated solar power system?
Answer: focus a large area of sunlight into a small beam

Question: What method does the photovoltaics system use to turn light into electricity?
Answer: photoelectric effect

Question: What has influenced the design since the beginning of architectural history?
Answer: Sunlight

Question: Who first utilized solar architecture?
Answer: Greeks and Chinese

Question: In which direction were the buildings built by the Greeks and Chinese facing?
Answer: toward the south

Question: What is a solar balloon?
Answer: a black balloon that is filled with ordinary air

Question: What happens when sunlight shines on a solar balloon?
Answer: the air inside is heated and expands causing an upward buoyancy force

Question: What is the use of solar balloons typically limited to?
Answer: the toy market

Question: Why is the use of solar balloons typically limited to the toy market?
Answer: the surface-area to payload-weight ratio is relatively high

Question: Why was solar technology developed in the 1860s?
Answer: driven by an expectation that coal would soon become scarce

Question: What slowed the development of solar technologies in the early 20th century?
Answer: increasing availability, economy, and utility of coal and petroleum

Question: According to a report in 2011, by what year could solar energy provide a third of the world's energy?
Answer: 2060

Question: What could the sun's energy do to help limit climate change?
Answer: could play a key role in de-carbonizing the global economy alongside improvements in energy efficiency and imposing costs on greenhouse gas emitters