Question: What were the areas at the center of an old sheet of glass called?
Answer: bull's-eyes

Question: In early 20th century glass production, the glass was thickest at what part of the sheet?
Answer: the center

Question: Currently window glass is made as what?
Answer: float glass

Question: How was the bull's-eye used?
Answer: for decorative effect

Question: What was the benefit of installing glass with the thick side at the bottom, in addition to avoiding water accumulation?
Answer: stability

Question: Who used to make window panes?
Answer: glassblowers

Question: What is the name for the glassmaking method that involved spinning it into sheets?
Answer: crown glass process

Question: The thickness at the bottom of glass panes was once taken as evidence that glass had features of what state of matter?
Answer: liquid

Question: When does glass stop moving like a liquid?
Answer: once solidified

Question: How is "glass" defined in physics?
Answer: a solid formed by rapid melt quenching

Question: What is the tendency to make a glass when cooled called?
Answer: glass-forming ability

Question: What must happen quickly for glass to form?
Answer: cooling

Question: What predicts glass-forming ability?
Answer: rigidity theory

Question: What does glass not have, leading some to think it is a liquid?
Answer: first-order phase transition

Question: What theory isn't completely valid for glass?
Answer: equilibrium theory of phase transformations

Question: Transition in glass is comparable to what?
Answer: a second-order phase transition

Question: Atomically, glass is similar to what?
Answer: a supercooled liquid

Question: What acts like a liquid but is under the freezing temperature?
Answer: A supercooled liquid

Question: Despite its atomic structure, cooled glass acts like what?
Answer: a solid

Question: In cooled glass, what types of movement stop?
Answer: rotational and translational

Question: What drives the wider acceptance of renewable energy technologies?
Answer: Public policy and political leadership

Question: Denmark has a committment to 100 percent renewable energy by what year?
Answer: 2050

Question: How many countries now have renewable energy policies?
Answer: 144

Question: How much was the total investment in renewable energy in 2012?
Answer: $244 billion

Question: Why did the total investment in renewable energy go down in 2012?
Answer: dramatically lower solar prices

Question: What  six were the top countries for investment in recent years?
Answer: China, Germany, Spain, the United States, Italy, and Brazil

Question: Who has shown support for ambitious renewable energy goals?
Answer: EU member countries

Question: What group polled the 27 EU member states in 2010?
Answer: Eurobarometer

Question: The goal was to increase the share of renewable energy in the EU by 20 percent in what year?
Answer: 2020

Question: By the end of 2011, total renewable power capacity worldwide exceeded what number?
Answer: 1,360 GW

Question: Renewables contributed what percentage to our energy consumption?
Answer: 19 percent

Question: Renewables contributed what percentage to our electricity generation?
Answer: 22 percent

Question: Who was the UN under-secretary in 2011?
Answer: Achim Steiner

Question: Between what years did worldwide renewable energy capacity grow at rates of 10 to 60 percent annually?
Answer: 2004 through 2009

Question: Who is Achim Steiner?
Answer: UN under-secretary general

Question: Which group projected that solar plant may produce most of the world's electricity within 50 years?
Answer: International Energy Agency

Question: Photovoltaic and solar-thermal plants may meet most of the world's demand for electricity by what year?
Answer: 2060

Question: Photovoltaic and solar-thermal plants may meet how much of the world's energy needs by 2060?
Answer: half

Question: Who led the world in renewable energy production in 2013?
Answer: China

Question: Since what year has production of solar cells in China expanded 100-fold?
Answer: 2005

Question: What is the main driver of reduced costs?
Answer: market expansion

Question: What is getting cheaper as a result of technilogical change?
Answer: Renewable energy technologies

Question: As of what year have there been substantial reductions in the cost of solar and wind technologies?
Answer: 2011

Question: What group stated that "cost reductions in critical technologies, such as wind and solar, are set to continue?"
Answer: IEA

Question: What is the most economic solution for new grid-connected capacity in areas with good resources?
Answer: Renewable energy

Question: What happens as the scope of economically viable applications increases?
Answer: the cost of renewable power falls

Question: What are now often the most economic solution for new generating capacity?
Answer: Renewable technologies

Question: What is one problem with biomass?
Answer: material directly combusted in cook stoves produces pollutants

Question: What can be economically competetive but may still require deployment support?
Answer: First-generation biomass technologies

Question: What is a fully maturing technology which offer a ready disposal mechanismm?
Answer: Biomass for heat and power

Question: What is the term referring to electricity generated by hydropower?
Answer: Hydroelectricity

Question: What is the most widely used form of renewable energy?
Answer: Hydroelectricity

Question: Hydroelectricity accounts for what percentage of global electricity generation?
Answer: Hydroelectricity

Question: Electricity production is expected to increase by what percentage each year for the next 25 years?
Answer: 3.1%

Question: Hydropower is produced in how many countries?
Answer: 150

Question: Which country is the largest hydroelectricity producer?
Answer: China

Question: What is the average cost of electricity from a hydro plant larger than 10 megawatts?
Answer: 3 to 5 U.S. cents per kilowatt-hour

Question: How many hydroelectricity plants are larger than 10 GW?
Answer: three

Question: What was the geothermal capacity in 1975?
Answer: 1 GW

Question: What was the geothermal capacity in 2008?
Answer: 10 GW

Question: In the Phillipines, geothermal represented what percentage of the total power mix at the end of 2008?
Answer: 17 percent

Question: Where have the majority of photovoltaic power stations been built?
Answer: Europe

Question: Where is Charanka Solar Park?
Answer: India

Question: Where is the Agua Caliente Solar Project located?
Answer: USA

Question: Where is Desert Sunlight Solar Farm currently under construction?
Answer: Riverside County, California

Question: Where is Desert Sunlight Solar Farm?
Answer: San Luis Obispo County, California

Question: Who is building The Califoria Valley Solar Ranch?
Answer: SunPower

Question: Global wind power installations increased by how much in 2010?
Answer: 35,800 MW

Question: China has how much wind power installed?
Answer: 42,300 MW

Question: In Denmark, wind power accounts for what percentage of electricity generated?
Answer: 19%

Question: In Spain, wind power accounts for what percentage of electricity generated?
Answer: 9%

Question: In Germany, wind power accounts for what percentage of electricity generated?
Answer: 6%

Question: How is the wind industry in the USA able to produce more power at lower cost?
Answer: by using taller wind turbines with longer blades

Question: How tall are new wind turbines that are being built in Indiana, Michigan and Ohio?
Answer: 300 feet to 400 feet above the ground

Question: Wind turbines in the USA can now compete with what type of fuel?
Answer: conventional fossil fuels like coal

Question: Prices have fallen as low as what price?
Answer: 4 cents per kilowatt-hour

Question: Where is the Ivanpah Solar Power Facility located?
Answer: California's Mojave Desert

Question: What is the world's largest solar-thermal power plant project currently under construction?
Answer: Ivanpah Solar Power Facility