rajpurkar/squad huggingface dataset:
Title: Solar_energy

In 1897, Frank Shuman, a U.S. inventor, engineer and solar energy pioneer built a small demonstration solar engine that worked by reflecting solar energy onto square boxes filled with ether, which has a lower boiling point than water, and were fitted internally with black pipes which in turn powered a steam engine. In 1908 Shuman formed the Sun Power Company with the intent of building larger solar power plants. He, along with his technical advisor A.S.E. Ackermann and British physicist Sir Charles Vernon Boys, developed an improved system using mirrors to reflect solar energy upon collector boxes, increasing heating capacity to the extent that water could now be used instead of ether. Shuman then constructed a full-scale steam engine powered by low-pressure water, enabling him to patent the entire solar engine system by 1912.

Question: What was the name of the inventor who built a solar engine in 1897?
Answer: Frank Shuman

Question: In what year was the Sun Power Company formed?
Answer: 1908

Question: Shuman patented his solar engine system in what year?
Answer: 1912

Question: Who is Frank Shuman?
Answer: a U.S. inventor, engineer and solar energy pioneer

Question: In what year did solar engine build his solar engine?
Answer: 1897

Question: What was the solar engine used to power?
Answer: steam engine

Question: In what year was the Sun Power Company established?
Answer: 1908

Question: In what year did Frank Shuman patent his solar engine?
Answer: 1912
Title: Solar_energy

Shuman built the world’s first solar thermal power station in Maadi, Egypt, between 1912 and 1913. Shuman’s plant used parabolic troughs to power a 45–52 kilowatts (60–70 hp) engine that pumped more than 22,000 litres (4,800 imp gal; 5,800 US gal) of water per minute from the Nile River to adjacent cotton fields. Although the outbreak of World War I and the discovery of cheap oil in the 1930s discouraged the advancement of solar energy, Shuman’s vision and basic design were resurrected in the 1970s with a new wave of interest in solar thermal energy. In 1916 Shuman was quoted in the media advocating solar energy's utilization, saying:

Question: Where did Shuman build the world's first solar thermal power station?
Answer: Maadi, Egypt

Question: How many liters of water per minute did Shuman's engine pump in litres?
Answer: 22,000

Question: In what decade were Shuman's ideas about solar energy revived?
Answer: the 1970s

Question: Where was the first solar thermal power plant built?
Answer: Maadi, Egypt

Question: What was used to power the plants engine?
Answer: parabolic troughs

Question: From what river did the engine pump water?
Answer: Nile River

Question: What slowed down the growth of solar energy?
Answer: the outbreak of World War I and the discovery of cheap oil

Question: When was the interest in solar energy restored?
Answer: the 1970s
Title: Solar_energy

Solar hot water systems use sunlight to heat water. In low geographical latitudes (below 40 degrees) from 60 to 70% of the domestic hot water use with temperatures up to 60 °C can be provided by solar heating systems. The most common types of solar water heaters are evacuated tube collectors (44%) and glazed flat plate collectors (34%) generally used for domestic hot water; and unglazed plastic collectors (21%) used mainly to heat swimming pools.

Question: According to Shuman, up to what percentage of domestic hot water can be  provided by solar heating systems?
Answer: 70

Question: What do Solar hot water systems use to heat water?
Answer: sunlight

Question: How much hot water can be produced by solar heating systems in low geographical latitudes?
Answer: 60 to 70% of the domestic hot water

Question: What is a common type of solar water heater?
Answer: evacuated tube collectors

Question: What type of solar water heater is used to heat pools?
Answer: unglazed plastic collectors
Title: Solar_energy

As of 2007, the total installed capacity of solar hot water systems is approximately 154 thermal gigawatt (GWth). China is the world leader in their deployment with 70 GWth installed as of 2006 and a long-term goal of 210 GWth by 2020. Israel and Cyprus are the per capita leaders in the use of solar hot water systems with over 90% of homes using them. In the United States, Canada and Australia heating swimming pools is the dominant application of solar hot water with an installed capacity of 18 GWth as of 2005.

Question: What was the total capacity of solar hot water systems in 2007 in gigawatts?
Answer: 154

Question: Over 90% of homes use solar hot water systems in which two countries?
Answer: Israel and Cyprus

Question: What is the capacity of a solar hot water system?
Answer: approximately 154 thermal gigawatt

Question: What country is the leader in the implementation of solar powered hot water systems?
Answer: China

Question: What percentage of households use solar hot water systems in Israel and Cyprus?
Answer: over 90%

Question: In what countries is the use to solar hot water used mainly for w=swimming pools?
Answer: United States, Canada and Australia
Title: Solar_energy

In the United States, heating, ventilation and air conditioning (HVAC) systems account for 30% (4.65 EJ/yr) of the energy used in commercial buildings and nearly 50% (10.1 EJ/yr) of the energy used in residential buildings. Solar heating, cooling and ventilation technologies can be used to offset a portion of this energy.

Question: What percentage of energy in commercial buildings comes from HVAC systems?
Answer: 50

Question: How much energy does an HVAC system use in commercial locations?
Answer: 30% (4.65 EJ/yr)

Question: How much energy does an HVAC system use in residential locations?
Answer: 50% (10.1 EJ/yr)

Question: What can be used to balance out a portion of the energy used by HVAC systems?
Answer: Solar heating, cooling and ventilation technologies
Title: Solar_energy

Thermal mass is any material that can be used to store heat—heat from the Sun in the case of solar energy. Common thermal mass materials include stone, cement and water. Historically they have been used in arid climates or warm temperate regions to keep buildings cool by absorbing solar energy during the day and radiating stored heat to the cooler atmosphere at night. However, they can be used in cold temperate areas to maintain warmth as well. The size and placement of thermal mass depend on several factors such as climate, daylighting and shading conditions. When properly incorporated, thermal mass maintains space temperatures in a comfortable range and reduces the need for auxiliary heating and cooling equipment.

Question: Materials that can be used to store heat are known as what kind of mass?
Answer: Thermal

Question: What is thermal mass?
Answer: any material that can be used to store heat

Question: What are typical thermal mass material?
Answer: stone, cement and water

Question: How is thermal mass used to keep buildings cool?
Answer: by absorbing solar energy during the day and radiating stored heat to the cooler atmosphere at night

Question: What is a something that determines the size of thermal mass?
Answer: climates

Question: What does thermal mass reduce the need for?
Answer: auxiliary heating and cooling equipment
Title: Solar_energy

A solar chimney (or thermal chimney, in this context) is a passive solar ventilation system composed of a vertical shaft connecting the interior and exterior of a building. As the chimney warms, the air inside is heated causing an updraft that pulls air through the building. Performance can be improved by using glazing and thermal mass materials in a way that mimics greenhouses.

Question: What kind of system is a solar chimney?
Answer: passive solar ventilation

Question: What is a solar chimney?
Answer: a passive solar ventilation system

Question: What is a solar chimney made of?
Answer: a vertical shaft connecting the interior and exterior of a building

Question: How can the performance of a solar chimney be improved?
Answer: by using glazing and thermal mass materials in a way that mimics greenhouses
Title: Solar_energy

Deciduous trees and plants have been promoted as a means of controlling solar heating and cooling. When planted on the southern side of a building in the northern hemisphere or the northern side in the southern hemisphere, their leaves provide shade during the summer, while the bare limbs allow light to pass during the winter. Since bare, leafless trees shade 1/3 to 1/2 of incident solar radiation, there is a balance between the benefits of summer shading and the corresponding loss of winter heating. In climates with significant heating loads, deciduous trees should not be planted on the Equator facing side of a building because they will interfere with winter solar availability. They can, however, be used on the east and west sides to provide a degree of summer shading without appreciably affecting winter solar gain.

Question: The placement of deciduous trees on the Equator facing side of a building can have a negative effect on solar availability in which season?
Answer: winter

Question: What is something that is used to control solar heating and cooling?
Answer: trees and plants

Question: How much solar radiation is blocked by leafless trees?
Answer: 1/3 to 1/2

Question: Why should trees not be planted on the side of a building facing the equator?
Answer: they will interfere with winter solar availability

Question: What side of a building should trees be planted without greatly affecting solar gain in the winter?
Answer: east and west
Title: Solar_energy

Solar cookers use sunlight for cooking, drying and pasteurization. They can be grouped into three broad categories: box cookers, panel cookers and reflector cookers. The simplest solar cooker is the box cooker first built by Horace de Saussure in 1767. A basic box cooker consists of an insulated container with a transparent lid. It can be used effectively with partially overcast skies and will typically reach temperatures of 90–150 °C (194–302 °F). Panel cookers use a reflective panel to direct sunlight onto an insulated container and reach temperatures comparable to box cookers. Reflector cookers use various concentrating geometries (dish, trough, Fresnel mirrors) to focus light on a cooking container. These cookers reach temperatures of 315 °C (599 °F) and above but require direct light to function properly and must be repositioned to track the Sun.

Question: Horace de Saussure built the first box cooker in what year?
Answer: 1767

Question: Reflector cookers can reach temperatures in Celsius of up to what?
Answer: 315

Question: What are solar cookers used for?
Answer: cooking, drying and pasteurization

Question: What are the 3 main categories of solar cookers?
Answer: box cookers, panel cookers and reflector cookers

Question: Who created the box cooker?
Answer: Horace de Saussure

Question: What is the typical temperature range for a box cooker?
Answer: 90–150 °C (194–302 °F)

Question: What do reflector cookers require to function?
Answer: direct light
Title: Solar_energy

Solar concentrating technologies such as parabolic dish, trough and Scheffler reflectors can provide process heat for commercial and industrial applications. The first commercial system was the Solar Total Energy Project (STEP) in Shenandoah, Georgia, USA where a field of 114 parabolic dishes provided 50% of the process heating, air conditioning and electrical requirements for a clothing factory. This grid-connected cogeneration system provided 400 kW of electricity plus thermal energy in the form of 401 kW steam and 468 kW chilled water, and had a one-hour peak load thermal storage. Evaporation ponds are shallow pools that concentrate dissolved solids through evaporation. The use of evaporation ponds to obtain salt from sea water is one of the oldest applications of solar energy. Modern uses include concentrating brine solutions used in leach mining and removing dissolved solids from waste streams. Clothes lines, clotheshorses, and clothes racks dry clothes through evaporation by wind and sunlight without consuming electricity or gas. In some states of the United States legislation protects the "right to dry" clothes. Unglazed transpired collectors (UTC) are perforated sun-facing walls used for preheating ventilation air. UTCs can raise the incoming air temperature up to 22 °C (40 °F) and deliver outlet temperatures of 45–60 °C (113–140 °F). The short payback period of transpired collectors (3 to 12 years) makes them a more cost-effective alternative than glazed collection systems. As of 2003, over 80 systems with a combined collector area of 35,000 square metres (380,000 sq ft) had been installed worldwide, including an 860 m2 (9,300 sq ft) collector in Costa Rica used for drying coffee beans and a 1,300 m2 (14,000 sq ft) collector in Coimbatore, India, used for drying marigolds.

Question: The Solar Total Energy Project had a field of how many parabolic dishes?
Answer: 114

Question: Are transpired collectors more or less cost-effective than glazed collection systems?
Answer: more

Question: What are some examples of solar concentrating technologies?
Answer: parabolic dish, trough and Scheffler reflectors

Question: What was the first commercial solar concentrating system?
Answer: Solar Total Energy Project (STEP) in Shenandoah, Georgia, USA

Question: What is one of the oldest uses of solar energy?
Answer: use of evaporation ponds to obtain salt from sea water

Question: What are some items used to dry clothes without the use of electricity?
Answer: Clothes lines, clotheshorses, and clothes racks

Question: What are Unglazed transpired collectors?
Answer: perforated sun-facing walls used for preheating ventilation air
Title: Solar_energy

Solar distillation can be used to make saline or brackish water potable. The first recorded instance of this was by 16th-century Arab alchemists. A large-scale solar distillation project was first constructed in 1872 in the Chilean mining town of Las Salinas. The plant, which had solar collection area of 4,700 m2 (51,000 sq ft), could produce up to 22,700 L (5,000 imp gal; 6,000 US gal) per day and operate for 40 years. Individual still designs include single-slope, double-slope (or greenhouse type), vertical, conical, inverted absorber, multi-wick, and multiple effect. These stills can operate in passive, active, or hybrid modes. Double-slope stills are the most economical for decentralized domestic purposes, while active multiple effect units are more suitable for large-scale applications.

Question: In what year was a large scale solar distillation project constructed in Las Salinas?
Answer: 1872

Question: What is used to make saline or brackish water drinkable?
Answer: Solar distillation

Question: By who was the first record of solar distillation done by?
Answer: 16th-century Arab alchemists

Question: When was the first large solar distillation plant created?
Answer: 1872

Question: How much water was produced by the plant?
Answer: 22,700 L (5,000 imp gal; 6,000 US gal) per day

Question: What is an example of a solar distillation design?
Answer: single-slope
Title: Solar_energy

Solar water disinfection (SODIS) involves exposing water-filled plastic polyethylene terephthalate (PET) bottles to sunlight for several hours. Exposure times vary depending on weather and climate from a minimum of six hours to two days during fully overcast conditions. It is recommended by the World Health Organization as a viable method for household water treatment and safe storage. Over two million people in developing countries use this method for their daily drinking water.

Question: Solar water disinfection is recommended by which organization?
Answer: the World Health Organization

Question: How long should the plastic bottles filled with water be exposed to sunlight during Solar water disinfection?
Answer: a minimum of six hours to two days during fully overcast conditions

Question: What does the World Health Organization say about Solar water disinfection?
Answer: a viable method for household water treatment and safe storage

Question: How many people use Solar water disinfection to disinfect their drinking water?
Answer: Over two million people in developing countries
Title: Solar_energy

Solar energy may be used in a water stabilisation pond to treat waste water without chemicals or electricity. A further environmental advantage is that algae grow in such ponds and consume carbon dioxide in photosynthesis, although algae may produce toxic chemicals that make the water unusable.

Question: What is a possible negative effect of algae in water stabilization ponds?
Answer: toxic chemicals

Question: For what reason would solar energy be used in a water stabilisation pond?
Answer: to treat waste water without chemicals or electricity

Question: What is a reason why the water from a water stabilisation pond may be unusable?
Answer: algae may produce toxic chemicals
Title: Solar_energy

Solar power is anticipated to become the world's largest source of electricity by 2050, with solar photovoltaics and concentrated solar power contributing 16 and 11 percent to the global overall consumption, respectively.

Question: By what year is solar power expected to become the world's greatest source of electricity?
Answer: 2050

Question: When is solar power is foreseen to become the largest source of electricity?
Answer: 2050
Title: Solar_energy

Commercial CSP plants were first developed in the 1980s. Since 1985 the eventually 354 MW SEGS CSP installation, in the Mojave Desert of California, is the largest solar power plant in the world. Other large CSP plants include the 150 MW Solnova Solar Power Station and the 100 MW Andasol solar power station, both in Spain. The 250 MW Agua Caliente Solar Project, in the United States, and the 221 MW Charanka Solar Park in India, are the world’s largest photovoltaic plants. Solar projects exceeding 1 GW are being developed, but most of the deployed photovoltaics are in small rooftop arrays of less than 5 kW, which are grid connected using net metering and/or a feed-in tariff. In 2013 solar generated less than 1% of the worlds total grid electricity.

Question: The largest solar power plant in the world is located in what desert?
Answer: the Mojave Desert

Question: Less than 1% of the world's total grid electricity was generated by solar energy in what year?
Answer: 2013

Question: What is the largest solar power plant in the world?
Answer: 354 MW SEGS CSP

Question: Where is the largest solar power plant in the world located?
Answer: Mojave Desert of California

Question: What are the largest photovoltaic solar power plants?
Answer: The 250 MW Agua Caliente Solar Project, in the United States, and the 221 MW Charanka Solar Park in India
Title: Solar_energy

In the last two decades, photovoltaics (PV), also known as solar PV, has evolved from a pure niche market of small scale applications towards becoming a mainstream electricity source. A solar cell is a device that converts light directly into electricity using the photoelectric effect. The first solar cell was constructed by Charles Fritts in the 1880s. In 1931 a German engineer, Dr Bruno Lange, developed a photo cell using silver selenide in place of copper oxide. Although the prototype selenium cells converted less than 1% of incident light into electricity, both Ernst Werner von Siemens and James Clerk Maxwell recognized the importance of this discovery. Following the work of Russell Ohl in the 1940s, researchers Gerald Pearson, Calvin Fuller and Daryl Chapin created the crystalline silicon solar cell in 1954. These early solar cells cost 286 USD/watt and reached efficiencies of 4.5–6%. By 2012 available efficiencies exceed 20% and the maximum efficiency of research photovoltaics is over 40%.

Question: In the 1880s, who constructed the first solar cell?
Answer: Charles Fritts

Question: In what year was the crystalline silicon solar cell constructed?
Answer: 1954

Question: What has happened to photovoltaic in the past 20 years?
Answer: evolved from a pure niche market of small scale applications towards becoming a mainstream electricity source

Question: What is a solar cell?
Answer: a device that converts light directly into electricity

Question: Who created the first solar cell?
Answer: Charles Fritts

Question: Who created the first solar cell using silver selenide in place of copper oxide?
Answer: Dr Bruno Lange

Question: Who created the crystalline silicon solar cell?
Answer: Gerald Pearson, Calvin Fuller and Daryl Chapin
Title: Solar_energy

Concentrating Solar Power (CSP) systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. The concentrated heat is then used as a heat source for a conventional power plant. A wide range of concentrating technologies exists; the most developed are the parabolic trough, the concentrating linear fresnel reflector, the Stirling dish and the solar power tower. Various techniques are used to track the Sun and focus light. In all of these systems a working fluid is heated by the concentrated sunlight, and is then used for power generation or energy storage.

Question: In all the different CSP systems, concentrated sunlight is used to heat what?
Answer: a working fluid

Question: What do Concentrating Solar Power systems use?
Answer: lenses or mirrors and tracking systems

Question: What is the heat generated from a Concentrating Solar Power system used for?
Answer: a heat source for a conventional power plant

Question: What is one of the most developed Concentrating Solar Power technologies?
Answer: the Stirling dish

Question: What do Concentrating Solar Power technologies have in common?
Answer: a working fluid is heated by the concentrated sunlight
Title: Solar_energy

The common features of passive solar architecture are orientation relative to the Sun, compact proportion (a low surface area to volume ratio), selective shading (overhangs) and thermal mass. When these features are tailored to the local climate and environment they can produce well-lit spaces that stay in a comfortable temperature range. Socrates' Megaron House is a classic example of passive solar design. The most recent approaches to solar design use computer modeling tying together solar lighting, heating and ventilation systems in an integrated solar design package. Active solar equipment such as pumps, fans and switchable windows can complement passive design and improve system performance.

Question: Socrate's what is a classic example of passive solar design?
Answer: Megaron House

Question: What is a common feature of passive solar architecture?
Answer: orientation relative to the Sun

Question: What is produced when the features of passive solar architecture are customized to the environment?
Answer: well-lit spaces that stay in a comfortable temperature range

Question: What is an example of passive solar design?
Answer: Socrates' Megaron House

Question: What kind of equipment can improve system performance?
Answer: pumps, fans and switchable windows