Renewable electricity generation can be categorized as hydroelectric and non-hydroelectric power. Analysts at BP report that non-hydroelectric renewable power consumption grew by a respectable 6.2% worldwide during 2013 (the latest year for which data is available). North American consumption increased by a substantial 15.0%.
World hydroelectric consumption increased by 2.9% during 2013. North American hydroelectric consumption increased by only 0.3%, after accounting for a 2.3% decline in the U.S. during a below-average year due to droughts.
Steady growth does not mean that renewables account for a large amount of the world’s energy. Instead, non-hydroelectric renewables as a percent of global electricity generation accounted for about 5.3% in 2013, up substantially from 3.9% in 2012. Coal, natural gas and nuclear energy remain primary sources of electric generation in most parts of the world.
U.S. electric power production from renewable sources was 12.8% of total electric power in 2013, up from 12.2% in 2012 and only about 7.6% in 1970. In this case, “renewable” includes conventional hydroelectric and geothermal, along with solar, wind and biomass. (In 1970, such production was almost entirely from hydro.)
Wind power has seen rapid growth worldwide. Major technological advances in wind turbines (including much larger blades creating very high output per turbine, along with blades that suffer very little downtime and are thus more efficient), along with massive government incentives encouraging investment in wind generation, have fueled turbine installation. In the U.S., wind power generation output grew dramatically, from 11,187 thousand megawatts in 2003 to 94,652 thousand in 2010 and approximately 177,203 thousand during 2014. (The 2014 figure is for a rolling 12-month period that ended in September 2014.)
The Global Wind Energy Council estimated total wind generation capacity worldwide at 318,137 megawatts in 2013, and forecast it to climb to 536,130 in 2017. As of September 2014, U.S. wind capacity was 62,300 megawatts, more than 13 times higher than it was in 2000.
Solar power is enjoying significant technological innovation. The important factors in solar are the percent of captured solar energy that is converted into electricity, which is climbing, and the cost per installed watt of potential output, which is declining. The International Energy Agency reports that installed global solar photovoltaic capacity was 4,184 megawatts at the end of 2005 within the IEA Photovoltaic Power System Program Member Countries. By 2011, that number had soared to 69,371 megawatts, and in 2013 it surged ahead to 125,000 megawatts.
Biomass energy includes the use of energy from waste, such as wood chips and landfills, and the production of bioethanol. It has been growing rapidly as well, both in the U.S. and elsewhere.
As for nuclear power, we are entering an era in which the construction of new nuclear generating plants is accelerating rapidly in China, where demand for electricity is booming and dozens of new nuclear plants are planned. Several new plants are also planned or underway in the UAE, India and South Korea. The UK plans two new plants as well.
It should be noted that the use of renewable sources does not always mean clean power generation. For example, burning wood or trash for energy under the wrong conditions can create significant pollution. Also, the clearing of land, such as rain forests, for planting of biomass to be used in ethanol or biodiesel refining can be highly destructive to the environment while creating huge quantities of carbon emissions. In addition, many types of renewable energy production require vast quantities of water.
In the U.S., emphasis on alternative energy and conservation has a varied history. The 1973 oil trade embargo staged by Persian Gulf producers greatly limited the supply of petroleum on the market and created an instant interest in energy conservation. Thermostats were turned to more efficient levels, solar water heating systems sprouted on the rooftops of American homes (including a system that was used for a few years at the White House) and tax credits were launched by various government agencies to encourage investment in more efficient systems that would utilize less oil, gasoline and electricity. Meanwhile, American motorists crawled through lengthy lines at filling stations trying to top off their tanks during the horrid days of gasoline rationing.
While some consumers maintained a keen interest in alternative energy from an environmentally friendly point of view, most Americans quickly forgot about energy conservation when the price of gasoline plummeted during the 1980s and 1990s. Gasoline prices as low as 99 cents per gallon were common for many years. As advancing technology made oil production and electricity generation much more efficient, a low commodity price trend kept market prices under control. As a result, Americans returned to ice-cold air-conditioned rooms and purchased giant, gas-guzzling SUVs, motor homes and motorboats. The median newly constructed American single-family home built in 1972 contained 1,520 square feet; by the beginning of 2015 it contained 2,600 square feet. More square footage means more lights, air conditioning and heating systems to power. Meanwhile, federal and state regulators made efforts to force automobile engines and industrial plants to operate in clean-air mode, largely through the use of advanced technologies, while requiring gasoline refiners to adopt an ever-widening web of additives and standards that would create cleaner-burning fuels.
Fortunately, the first energy crisis in the early 1970s did lead to the use of technology to create significant efficiencies in some areas. For example, prior to that time, as much as 40% of a typical household’s natural gas consumption was for pilot lights burning idly in case a stove or furnace was needed. Today, electric pilots create spark ignition on demand. Likewise, today’s refrigerators use about 70% less electricity than models built in 1970. Many other appliances and electrical devices have become much more efficient. While the number of electricity-burning personal computers proliferated, computer equipment makers rapidly adopted energy-saving PC technologies.
Fluctuating oil and gas prices, along with tax credits and other incentives, have created a renewed interest in all things energy-efficient. Smaller cars, high-efficiency homes and solar power are once again part of popular culture. At the same time, renewable energy sources and cleaner-burning fuels are of great appeal to the large number of American consumers who have developed a true interest in protecting the environment. For example, surveys have shown that some consumers would be willing to pay somewhat more for electricity if they knew it was coming from non-polluting, renewable sources.
Hybrid gasoline-electric automobiles made by Toyota and Honda are selling well in the U.S. and elsewhere. “Clean diesel” cars that deliver very high mileage are extremely popular in Europe, and diesel cars made by Volkswagen and Mercedes are becoming more common in America. Ford has adopted aluminum as a primary metal for its popular F150 pickup trucks, savings hundreds of pounds in weight per truck and dramatically increasing fuel efficiency. Fuel cell-powered automobiles will be coming on the market in limited quantities in 2015 and 2016.
Meanwhile, many municipalities, such as the city of Seattle, Washington, have invested in buses and other vehicles that are hybrids or run on natural gas. Plug-in hybrid electric vehicles, and fully electric cars, are on the market worldwide, but sales are relatively slow due to high prices and limited range—better, cheaper batteries are needed to boost this sector.
Alternative energy is also attracting strong interest from investors. Globally, venture capital has helped to support innovation at firms that focus on alternative energy or energy conservation technologies. Likewise, national governments are helping to fund many energy efficiency projects, ranging from fuel cell research to the design and development of high-efficiency buildings, although these government-backed efforts sometimes lead to very large, very disappointing failures.
Legislation at state and national levels will continue to boost renewable energy development and conservation technologies on a global basis. In the U.S., governments in about 30 of the 50 states have passed stringent legislation requiring that an ever-growing percentage of electric generation comes from renewable means.
Technologies with a reliable return on investment, such as hydroelectric, remain extremely desirable. Conservation through advanced materials and technologies, such as retrofitting existing buildings with more efficient windows, insulation and air conditioning, is growing, and a good return on investment and an increase in property values are typical results. Alternative oil sources, such as oil sands and oil shale, harbor vast potential reserves, but they are a challenge to produce at reasonable prices per barrel of oil equivalent.
Bioethanol and biodiesel, from an economic and environmental point of view, are questionable at the least, and extremely misdirected at the worst. Some production of bioethanol appears very efficient, particularly in Brazil where sugar cane is the feedstock. However, the diversion of corn and soy from the food chain to the energy chain for ethanol or biodiesel may be a very bad idea from a wide variety of measures. Advanced technologies that capture carbon dioxide and utilize it to grow oil-producing algae appear to be a promising alternative, but much research and development remains to be done in this area.
At least two geothermal energy projects, where deep holes are drilled to tap the high temperatures of the inner Earth, have recently been cancelled due to concerns that these activities cause earthquakes. Tidal energy looks promising, but both installation costs and maintenance remain huge obstacles.
The bottom line is that many types of renewable energy production simply cannot exist without substantial government investments, incentives, loans and/or tax breaks. Hydroelectric is a rare exception, as it produces power at very low cost. In nearly all other cases, large-scale projects based on solar, wind or wave power can only be funded through high levels of government support. Consumers of such power will pay much higher rates for electricity, either directly through their power bills or indirectly through their taxes. It remains to be seen whether technologies in these fields can advance to the point that these renewable power sources can become economically viable on a self-sustaining basis.
Smaller-scale, rooftop solar power installations have become extremely popular in sunny climates in the U.S. and elsewhere. The cost of solar cells has plummeted to the point that solar power produced at homes and commercial buildings are becoming economically viable after government incentives are factored in. While the solar cells themselves are now relatively cheap, installation remains costly. Meanwhile, solar cells require regular maintenance, and their efficiency degrades steadily over time.
The renewable energy sector will continue to evolve rapidly, as new technologies offer breakthroughs and greater efficiencies are reached. The biggest gains will occur when powerful new batteries are finally developed that make it cost-effective to store solar and wind power where they are produced, for release as needed even when wind or sunlight are not available.
Video Introduction to Renewable & Alternative Energy Industry