Wind and solar power are even more expensive than is commonly thought ... SUBSIDIES for renewable energy are one of the most contested areas of public policy. Billions are spent nursing the infant solar- and wind-power industries in the hope that they will one day undercut fossil fuels and drastically reduce the amount of carbon dioxide being put into the atmosphere. The idea seems to be working. Photovoltaic panels have halved in price since 2008 and the capital cost of a solar-power plant—of which panels account for slightly under half—fell by 22% in 2010-13. In a few sunny places, solar power is providing electricity to the grid as cheaply as conventional coal- or gas-fired power plants. ... But whereas the cost of a solar panel is easy to calculate, the cost of electricity is harder to assess. It depends not only on the fuel used, but also on the cost of capital (power plants take years to build and last for decades), how much of the time a plant operates, and whether it generates power at times of peak demand. To take account of all this, economists use “levelised costs”—the net present value of all costs (capital and operating) of a generating unit over its life cycle, divided by the number of megawatt-hours of electricity it is expected to supply. ... The trouble, as Paul Joskow of the Massachusetts Institute of Technology has pointed out, is that levelised costs do not take account of the costs of intermittency.* Wind power is not generated on a calm day, nor solar power at night, so conventional power plants must be kept on standby—but are not included in the levelised cost of renewables. Electricity demand also varies during the day in ways that the supply from wind and solar generation may not match, so even if renewable forms of energy have the same levelised cost as conventional ones, the value of the power they produce may be lower. In short, levelised costs are poor at comparing different forms of power generation. ... the most cost-effective zero-emission technology is nuclear power.

Coal? Or the Sun? The power source India chooses may decide the fate of the entire planet. ... Already Earth’s fastest-growing major economy and its biggest weapons importer, India is on track to become the world’s most populous nation (probably by 2022), to have its biggest economy (possibly by 2048), and potentially to build its biggest military force (perhaps by 2040). What China was in the American imagination in the 1990s and 2000s, India will be in the next two decades—a cavalcade of superlatives, a focus of fears. ... officials and academics have long argued that Western nations are demanding that India industrialize without burning even a fraction of the fossil fuels that developed nations consumed when they industrialized. And Indians resent that Western nations insist on the right to judge Indian performance while refusing to help with the cost of transition. ... India’s demand for electricity is widely expected to double by 2030. …= Soon after being elected prime minister in 2014, he announced that India would produce 100 gigawatts of solar power by 2022 (the US now has about 20 gigawatts). ... To generate electricity from it, India plans to build 455 new coal-fired electric power plants, more than any other nation—indeed, more than the US now has. (India’s existing 148 plants, which provide two-thirds of its electricity, are among the world’s dirtiest and most inefficient.)

A critical part of any analysis of high-renewable systems is the cost of backup thermal power and/or storage needed to meet demand during periods of low renewable generation. These costs are substantial; as a result, levelized costs of wind and solar are not the right tools to use in assessing the total cost of a high-renewable system ... High-renewable grids reduce CO2 emissions by 65%-70% in Germany and 55%-60% in California vs. the current grid. Reason: backup thermal capacity is idle for much of the year ... High-renewable grid costs per MWh are 1.9x the current system in Germany, and 1.5x in California. Costs fall to 1.6x in Germany and 1.2x in California assuming long-run “learning curve” declines in wind, solar and storage costs, higher nuclear plant costs and higher natural gas fuel costs ... The cost of time-shifting surplus renewable generation via storage has fallen, but its cost, intermittent utilization and energy loss result in higher per MWh system costs when it is added ... Balanced systems with nuclear power have lower estimated costs and CO2 emissions than high-renewable systems. However, there’s enormous uncertainty regarding the actual cost of nuclear power in the US and Europe, rendering balanced system assessments less reliable. Nuclear power is growing in Asia where plant costs are 20%-30% lower, but political, historical, economic, regulatory and cultural issues prevent these observations from being easily applied outside of Asia ... National/cross-border grid expansion, storing electricity in electric car batteries, demand management and renewable energy overbuilding are often mentioned as ways of reducing the cost of high-renewable systems. However, each relies to some extent on conjecture, insufficient empirical support and/or incomplete assessments of related costs

Warren Buffett controls Nevada’s legacy utility. Elon Musk is behind the solar company that’s upending the market. Let the fun begin. ... SolarCity’s success is partly because the government provides subsidies and enables an arrangement called net metering, which allows homeowners with panels to sell back to the grid any solar energy they don’t use. This helps offset their cost of power when the sun’s not shining. Like more than 40 other U.S. states, Nevada forces utilities to buy the excess energy at rates set by regulators—usually the same rate utilities charge (hence, the net in net metering). In Nevada, it’s worked well. So well, in fact, that NV Energy, the state’s largest utility, is fighting it with everything it’s got. ... In just a decade, solar has gone from an enviro’s dream to a serious lobby that will be fighting these kinds of battles nationwide for years. ... Power companies may not be winning any popularity contests, but they’re developing their own renewable energy to keep up with changing attitudes and to meet state mandates.

Immune Engineering: Genetically engineered immune cells are saving the lives of cancer patients. That may be just the start.
Precise Gene Editing in Plants: CRISPR offers an easy, exact way to alter genes to create traits such as disease resistance and drought tolerance.
Conversational Interfaces: Powerful speech technology from China’s leading Internet company makes it much easier to use a smartphone.
Reusable Rockets: Rockets typically are destroyed on their maiden voyage. But now they can make an upright landing and be refueled for another trip, setting the stage for a new era in spaceflight.
Robots That Teach Each Other: What if robots could figure out more things on their own and share that knowledge among themselves?
DNA App Store: An online store for information about your genes will make it cheap and easy to learn more about your health risks and predispositions.
SolarCity’s Gigafactory: A $750 million solar facility in Buffalo will produce a gigawatt of high-efficiency solar panels per year and make the technology far more attractive to homeowners.
Slack: A service built for the era of mobile phones and short text messages is changing the workplace.
Tesla Autopilot: The electric-vehicle maker sent its cars a software update that suddenly made autonomous driving a reality.
Power from the Air: Internet devices powered by Wi-Fi and other telecommunications signals will make small computers and sensors more pervasive.

In the industrialized world, the power grid is so reliable that we take it for granted. But in India, where blackouts are a sad fact of daily life, being connected to the grid is no guarantee of reliable electricity. In a 2015 study of villages in six Indian states [PDF], for example, the vast majority reported having fewer than 4 hours of electricity per day; nearly half of the households that reported having a grid connection nevertheless had effectively no electricity. Chief among the reasons they cited were poor reliability, quality, and affordability. In many parts of the country, even middle-income households still find themselves held hostage to frequent power cuts that can last anywhere from a few hours a day to most of the day. Those who can afford to often install diesel generators, an expensive and polluting option. ... Then, too, roughly a quarter of a billion Indians, or one-fifth of the population, live without access to any electricity at all ... The Indian government has taken a traditional approach to electrification, which focuses on building up generation, transmission, and distribution. But there’s a better way that’s more affordable, more efficient, and much faster and easier to deploy.

There are about as many people living without electricity today as there were when Thomas Edison lit his first light bulb. More than half are in sub-Saharan Africa. Europe and the Americas are almost fully electrified, and Asia is quickly catching up, but the absolute number of Africans without power remains steady. A World Bank report, released in May, predicted that, given current trends, there could still be half a billion people in sub-Saharan Africa without power by 2040. Even those with electricity can’t rely on it: the report noted that in Tanzania power outages were so common in 2013 that they cost businesses fifteen per cent of their annual sales. Ghanaians call their flickering power dum/sor, or “off/on.” Vivian Tsadzi, a businesswoman who lives not far from the Akosombo Dam, which provides about a third of the nation’s power, said that most of the time “it’s dum dum dum dum.” The dam’s head of hydropower generation, Kwesi Amoako, who retired last year, told me that he is proud of the structure, which created the world’s largest man-made lake. But there isn’t an easy way to increase the country’s hydropower capacity, and drought, caused by climate change, has made the system inconsistent, meaning that Ghana will have to look elsewhere for electricity. “I’ve always had the feeling that one of the main thrusts should be domestic solar,” Amoako said. “And I think we should put the off-grid stuff first, because the consumer wants it so badly.” ... Electrifying Africa is one of the largest development challenges on earth. Until recently, most people assumed that the continent would electrify in the same manner as the rest of the globe. ... Solar electricity, on the other hand, has become inexpensive, in part because the price of solar panels has fallen at the same time that the efficiency of light bulbs and appliances has dramatically increased. ... It will be years before it makes financial sense for solar companies to expand to the most remote and challenging regions of the continent.