100% renewable energy

The wind, Sun, and biomass are three renewable energy sources

The incentive to use 100% renewable energy, for electricity, transport, or even total primary energy supply globally, has been motivated by global warming and other ecological as well as economic concerns. Renewable energy use has grown much faster than anyone anticipated.^[1] The Intergovernmental Panel on Climate Change has said that there are few fundamental technological limits to integrating a portfolio of renewable energy technologies to meet most of total global energy demand.^[2] At the national level, at least 30 nations around the world already have renewable energy contributing more than 20% of energy supply. Also, Professors S. Pacala and Robert H. Socolow have developed a series of “stabilization wedges” that can allow us to maintain our quality of life while avoiding catastrophic climate change, and "renewable energy sources," in aggregate, constitute the largest number of their "wedges." ^[3]

Mark Z. Jacobson says producing all new energy with wind power, solar power, and hydropower by 2030 is feasible and existing energy supply arrangements could be replaced by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Jacobson says that energy costs with a wind, solar, water system should be similar to today's energy costs.^[4]

Similarly, in the United States, the independent National Research Council has noted that “sufficient domestic renewable resources exist to allow renewable electricity to play a significant role in future electricity generation and thus help confront issues related to climate change, energy security, and the escalation of energy costs … Renewable energy is an attractive option because renewable resources available in the United States, taken collectively, can supply significantly greater amounts of electricity than the total current or projected domestic demand." .^[5]

Critics of the "100% renewable energy" approach include Vaclav Smil and James E. Hansen. Smil and Hansen are concerned about the variable output of solar and wind power; but, as Amory B. Lovins noted: "U.S. and European studies have shown how whole continents could make 80 percent or more of their power renewably."^[6]

History

In 1976 energy policy analyst Amory Lovins coined the term "soft energy path" to describe an alternative future where energy efficiency and appropriate renewable energy sources steadily replace a centralized energy system based on fossil and nuclear fuels.^[7] Even a decade ago it was extraordinary for scientists and decision-makers to consider the concept of 100 per cent renewable electricity. However, renewable energy progress has been so rapid that things have totally changed since then:^[8]

Solar photovoltaic modules have dropped about 75 per cent in price. Current scientific and technological advances in the laboratory suggest that they will soon be so cheap that the principal cost of going solar on residential and commercial buildings will be installation. On-shore wind power is spreading over all continents and is economically competitive with fossil and nuclear power in several regions. Concentrated solar thermal power (CST) with thermal storage has moved from the demonstration stage of maturity to the limited commercial stage and still has the potential for further cost reductions of about 50 per cent.^[8]

Renewable energy use has grown much faster than anyone anticipated.^[1] Wind turbines generate nearly 30 percent of Danish electricity, and Denmark has many biogas digesters and waste-to-energy plants as well. Together, wind and biomass provide 44% of the electricity consumed by the country's six million inhabitants. In 2010, Portugal’s 10 million people produced more than half their electricity from indigenous renewable energy resources. Spain’s 40 million inhabitants meet one-third of their electrical needs from renewables.^[1]

Renewable energy has a history of strong public support. In America, for example, a 2013 Gallup survey showed that two in three Americans want the U.S. to increase domestic energy production using solar power (76%), wind power (71%), and natural gas (65%). Far fewer want more petroleum production (46%) and more nuclear power (37%). Least favored is coal, with about one in three Americans favouring it.^[9]

REN21 says renewable energy already plays a significant role and there are many policy targets which aim to increase this:

At the national level, at least 30 nations around the world already have renewable energy contributing more than 20% of energy supply. National renewable energy markets are projected to continue to grow strongly in the coming decade and beyond, and some 120 countries have various policy targets for longer-term shares of renewable energy, including a binding 20% by 2020 target for the European Union. Some countries have much higher long-term policy targets of up to 100% renewables. Outside Europe, a diverse group of 20 or more other countries target renewable energy shares in the 2020–2030 time frame that range from 10% to 50%.^[10]

A well established body of academic literature has been established over a the past decade, evaluating scenarios for 100% renewable energy for various geographical areas. In recent years, more detailed analyses have emerged from government and industry sources.^[11] The incentive to use 100% renewable energy is created by global warming and ecological as well as economic concerns, post peak oil. The first country to propose 100% renewable energy was Iceland, in 1998.^[12] Proposals have been made for Japan in 2003,^[13] and for Australia in 2011.^[14] Norway and some other countries already obtain all of their electricity from renewable sources. Iceland proposed using hydrogen for transportation and its fishing fleet. Australia proposed biofuel for those elements of transportation not easily converted to electricity. The road map for the United States,^[15][16] commitment by Denmark,^[17] and Vision 2050 for Europe set a 2050 timeline for converting to 100% renewable energy,^[18] later reduced to 2040 in 2011.^[19] Zero Carbon Britain 2030 proposes eliminating carbon emissions in Britain by 2030 by transitioning to renewable energy.^[20]

It is estimated that the world will spend an extra $8 trillion over the next 25 years to prolong the use of non-renewable resources, a cost that would be eliminated by transitioning instead to 100% renewable energy.^[21] A 2009 study suggests that converting the entire world to 100% renewable energy by 2030 is both possible and affordable, but requires political support. It would require building many more wind turbines and solar power systems. Other changes involve use of electric cars and the development of enhanced transmission grids and storage.^{[22][23][24][25][26]}

Recent developments

The Fourth Revolution: Energy is a German documentary film released in 2010. It shows the vision of a global society, which lives in a world where the energy is produced 100% with renewable energies, showing a complete reconstruction of the economy, to reach this goal. In 2011, Hermann Scheer wrote the book The Energy Imperative: 100 Percent Renewable Now, published by Routledge.

In 2011, the Intergovernmental Panel on Climate Change, the world's leading climate researchers selected by the United Nations, said "as infrastructure and energy systems develop, in spite of the complexities, there are few, if any, fundamental technological limits to integrating a portfolio of renewable energy technologies to meet a majority share of total energy demand in locations where suitable renewable resources exist or can be supplied".^[2] IPCC scenarios "generally indicate that growth in renewable energy will be widespread around the world".^[27] The IPCC said that if governments were supportive, and the full complement of renewable energy technologies were deployed, renewable energy supply could account for almost 80% of the world's energy use within forty years.^[28] Rajendra Pachauri, chairman of the IPCC, said the necessary investment in renewables would cost only about 1% of global GDP annually. This approach could contain greenhouse gas levels to less than 450 parts per million, the safe level beyond which climate change becomes catastrophic and irreversible.^[28]

Reinventing Fire is a book by Amory Lovins released in October 2011. By combining reduced energy use with energy efficiency gains, Lovins says that there will be a $5 trillion saving and a faster-growing economy. This can all be done with the profitable commercialization of existing energy-saving technologies, through market forces, led by business.^[29] Bill Clinton says the book is a "wise, detailed and comprehensive blueprint".^[30] The first paragraph of the preface says:

Imagine fuel without fear. No climate change. No oil spills, dead coal miners, dirty air, devastated lands, lost wildlife. No energy poverty. No oil-fed wars, tyrannies, or terrorists. Nothing to run out. Nothing to cut off. Nothing to worry about. Just energy abundance, benign and affordable, for all, for ever.^[31]

In 2011, the International Energy Agency has said that solar energy technologies, in its many forms, can make considerable contributions to solving some of the most urgent problems the world now faces:^[32]

The development of affordable, inexhaustible and clean solar energy technologies will have huge longer-term benefits. It will increase countries’ energy security through reliance on an indigenous, inexhaustible and mostly import-independent resource, enhance sustainability, reduce pollution, lower the costs of mitigating climate change, and keep fossil fuel prices lower than otherwise. These advantages are global. Hence the additional costs of the incentives for early deployment should be considered learning investments; they must be wisely spent and need to be widely shared.^[32]

In 2011, the refereed journal Energy Policy published two articles by Mark Z. Jacobson, a professor of engineering at Stanford University, and research scientist Mark A. Delucchi, about changing our energy supply mix and "Providing all global energy with wind, water, and solar power". The articles analyze the feasibility of providing worldwide energy for electric power, transportation, and heating/cooling from wind, water, and sunlight (WWS), which are safe clean options. In Part I, Jacobson and Delucchi discuss WWS energy system characteristics, aspects of energy demand, WWS resource availability, WWS devices needed, and material requirements.^[33] They estimate that 3,800,000 5 MW wind turbines, 5350 100 MW geothermal power plants, and 270 new 1300 MW hydroelectric power plants will be required. In terms of solar power, an additional 49,000 300 MW concentrating solar plants, 40,000 300 MW solar photovoltaic power plants, and 1.7 billion 3 kW rooftop photovoltaic systems will also be needed. Such an extensive WWS infrastructure could decrease world power demand by 30%.^[33] In Part II, Jacobson and Delucchi address variability of supply, system economics, and energy policy initiatives associated with a WWS system. The authors advocate producing all new energy with WWS by 2030 and replacing existing energy supply arrangements by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Energy costs with a WWS system should be similar to today's energy costs.^[4]

In general, Jacobson has said wind, water and solar technologies can provide 100 per cent of the world's energy, eliminating all fossil fuels.^[34] He advocates a "smart mix" of renewable energy sources to reliably meet electricity demand:

Because the wind blows during stormy conditions when the sun does not shine and the sun often shines on calm days with little wind, combining wind and solar can go a long way toward meeting demand, especially when geothermal provides a steady base and hydroelectric can be called on to fill in the gaps.^[35]

A 2012 study by the University of Delaware for a 72 GW system considered 28 billion combinations of renewable energy and storage and found the most cost-effective, for the PJM Interconnection, would use 17 GW of solar, 68 GW of offshore wind, and 115 GW of onshore wind, although at times as much as three times the demand would be provided. 0.1% of the time would require generation from other sources.^[36]

In March 2012, Denmark's parliament agreed on a comprehensive new set promotional programs for energy efficiency and renewable energy that will lead to the country getting 100 percent of electricity, heat and fuels from renewables by 2050.^[37] IRENEC is an annual conference on 100% renewable energy started in 2011 by EUROSOLAR Turkey. The 2013 conference is scheduled for June 27–29 in Istanbul.^[38][39]

Barriers

NASA Climate scientist James Hansen has said that while it is conceivable in places such as New Zealand and Norway, "suggesting that renewables will let us phase rapidly off fossil fuels in the United States, China, India, or the world as a whole is almost the equivalent of believing in the Easter Bunny and Tooth Fairy."^[40][41] In 2013, Smil analyzed proposals to depend on wind and solar-generated electricity including the proposals of Jacobson and colleagues, and writing in an issue of Spectrum prepared by the Institute of Electrical and Electronics Engineers, he identified numerous points of concern, such as cost, intermittent power supply, growing NIMBYism, and a lack of infrastructure as negative factors and said that "History and a consideration of the technical requirements show that the problem is much greater than these advocates have supposed."^[40][42]

Smil and Hansen are concerned about the variable output of solar and wind power, but many other scientists and engineers have analysed this situation and said that the electricity grid can cope.^[6] Amory Lovins says this about the electricity grid:

Just as it routinely backs up nonworking coal-fired and nuclear plants with working ones, it can back up becalmed wind turbines or darkened solar cells with flexible generators (renewable or not) in other places or of other kinds, or with systems that voluntarily modulate demand. Even with little or no bulk power storage, diversified, forecastable, and integrated renewables can prove highly reliable. Such integration into a larger, more diverse grid is how in 2010 Denmark had the capacity to produce 36 percent of its electricity from renewables, including 26 percent from wind (in an average wind year), and how four German states were 43–52 percent wind-powered. But U.S. and European studies have shown how whole continents could make 80 percent or more of their power renewably by operating existing assets differently within smarter grids, in markets that clear faster and serve larger areas. Diverse, dispersed, renewable sources can also make the grid highly resilient. Centralized grids are vulnerable to cascading blackouts caused by natural disaster, accident, or malice.^[6]

The most significant barriers to the widespread implementation of large-scale renewable energy and low carbon energy strategies, at the pace required to prevent runaway climate change, are primarily political and not technological. According to the 2013 Post Carbon Pathways report, which reviews many international studies, the key roadblocks are:^[43]

• Climate change denial
• The power of the fossil fuel industry and its allies
• Political paralysis
• Unsustainable consumption of energy and resources
• Path dependencies and outdated infrastructure
• Financial and governance constraints

See also

• Energy transition
• Energy Transition in Germany
• List of countries by renewable electricity production
• List of energy storage projects
• Germany National Renewable Energy Action Plan

References