A more recent concept for improving our electrical grid is to beam microwaves from Earth-orbiting satellites or the moon to directly when and where there is demand. The power would be generated from solar energy captured on the lunar surface In this system, the receivers would be “broad, translucent tent-like structures that would receive microwaves and convert them to electricity”. NASA said in 2000 that the technology was worth pursuing but it is still too soon to say if the technology will be cost-effective.
This uncertainty about the most practical financial model reflects the fact that in sub-Saharan Africa there soalr energy a great deal of economic diversity, both between countries and within them. One morning, I found myself walking down a line of houses in the Arushan suburb of Morombo. At the first house, a two-room cinder-block structure with a broken piece of mirror on one wall, a woman talked with me as we sat on the floor. The home represented a big step up for her, she said—she and her husband had rented a place for years, until they were able to buy this plot of land and build this house. She had a solar lantern the size of a hockey puck in her courtyard, soaking up rays. (Aid groups have distributed more than a million of these little lamps across the continent.) She assured me that she planned to get a larger solar system soon, but, for many of Africa’s poorest people, buying a lantern is the only possible step toward electrification.
The Energy Policy Act of 2005 requires all public electric utilities to facilitate net metering. This allows homes and businesses performing distributed generation to pay only the net cost of electricity from the grid: electricity used minus electricity produced locally and sent back into the grid. For intermittent renewable energy sources this effectively uses the grid as a battery to smooth over lulls and fill in production gaps.
The basis of producing solar panels revolves around the use of silicon cells. These silicon cells are typically 10-20% efficient at converting sunlight into electricity, with newer production models now exceeding 22%.
But CAISO concedes that curtailments and “negative pricing” is likely to happen even more often in the future as solar power production continues to grow, unless action is taken to better manage the excess electricity.
The United States consumed about 4,000 TWh of electricity in 2012, and about 98 quadrillion BTU (30,000 TWh) of primary energy. Efficiency improvements are expected to reduce usage to 15,000 TWh by 2050.
In 1839, a nineteen year-old French physicist named Alexandre-Edmond Becquerel discovered the operating principle of the solar cell, known as the photovoltaic effect. It wasn’t until 1876 that this effect materialized into a viable method of producing electricity with the work of William Grylls Adams. He discovered that by illuminating a junction between selenium and platinum, a photovoltaic effect occurs; electricity could now be produced without moving parts.
Big utilities continue to push for all of the plants, maintaining that building natural gas plants doesn’t conflict with expanding solar power. They say both paths are necessary to ensure that California has reliable sources of power — wherever and whenever it is needed.
In several countries with common carrier arrangements, electricity retailing arrangements make it possible for consumers to purchase green electricity (renewable electricity) from either their utility or a green power provider.
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.”
The NFPA and ICC publish their codes as model documents. It’s up to individual counties to decide which edition to implement, and if they want to make adjustments on a local level. “You can go across the country and some are on the 2015 [codes] already, some are on the 2012, some on 2009,” says fire code consultant Bob Davidson, who helps write the codes. Florida uses the 2012 NFPA code. Alabama, right next door, still uses the 2009 version of the International Fire Code.
In contrast, most renewable energy sources produce little to no global warming emissions. Even when including “life cycle” emissions of clean energy (ie, the emissions from each stage of a technology’s life—manufacturing, installation, operation, decommissioning), the global warming emissions associated with renewable energy are minimal .
Grid parity, the point at which the cost of photovoltaic electricity is equal to or cheaper than the price of grid power, is more easily achieved in areas with abundant sun and high costs for electricity such as in California and Japan. In 2008, The levelized cost of electricity for solar PV was $0.25/kWh or less in most of the OECD countries. By late 2011, the fully loaded cost was predicted to fall below $0.15/kWh for most of the OECD and to reach $0.10/kWh in sunnier regions. These cost levels are driving three emerging trends: vertical integration of the supply chain, origination of power purchase agreements (PPAs) by solar power companies, and unexpected risk for traditional power generation companies, grid operators and wind turbine manufacturers.[dead link]
Producing electricity from solar energy was the second discovery. In 1839 a French physicist named Edmund Becquerel realized that the sun’s energy could produce a “photovoltaic effect” (photo = light, voltaic = electrical potential). In the 1880s, selenium photovoltaic (PV) cells were developed that could convert light into electricity with 1-2% efficiency (“the efficiency of a solar cell is the percentage of available sunlight converted by the photovoltaic cell into electricity”), but how the conversion happened was not understood. Photovoltaic power therefore “remained a curiosity for many years, since it was very inefficient at turning sunlight into electricity.” It was not until Albert Einstein proposed an explanation for the “photoelectric effect” in the early 1900s, for which he won a Nobel Prize, that people began to understand the related photovoltaic effect.
The smallest photovoltaic systems power calculators and wrist watches. Larger systems can provide electricity to pump water, to power communications equipment, to supply electricity for a single home or business, or to form large arrays that supply electricity to thousands of electricity consumers.
United Nations’ Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. In October 2011, he “announced the creation of a high-level group to drum up support for energy access, energy efficiency and greater use of renewable energy. The group is to be co-chaired by Kandeh Yumkella, the chair of UN Energy and director general of the UN Industrial Development Organisation, and Charles Holliday, chairman of Bank of America”.
The combination of wind and solar PV has the advantage that the two sources complement each other because the peak operating times for each system occur at different times of the day and year. The power generation of such solar hybrid power systems is therefore more constant and fluctuates less than each of the two component subsystems. Solar power is seasonal, particularly in northern/southern climates, away from the equator, suggesting a need for long term seasonal storage in a medium such as hydrogen or pumped hydroelectric. The Institute for Solar Energy Supply Technology of the University of Kassel pilot-tested a combined power plant linking solar, wind, biogas and hydrostorage to provide load-following power from renewable sources.
The movement of wind and water, the heat and light of the sun, the carbohydrates in plants, and the warmth in the Earth—all are energy sources that can supply our needs in a sustainable way. A variety of methods are used to convert these renewable resources into electricity. Each comes with its own unique set of technologies, benefits, and challenges.
Scientists from Spectrolab, a subsidiary of Boeing, have reported development of multi-junction solar cells with an efficiency of more than 40%, a new world record for solar photovoltaic cells. The Spectrolab scientists also predict that concentrator solar cells could achieve efficiencies of more than 45% or even 50% in the future, with theoretical efficiencies being about 58% in cells with more than three junctions.
Technologies promote sustainable energy including renewable energy sources, such as hydroelectricity, solar energy, wind energy, wave power, geothermal energy, bioenergy, tidal power and also technologies designed to improve energy efficiency. Costs have decreased immensely throughout the years, and continue to fall. Increasingly, effective government policies support investor confidence and these markets are expanding. Considerable progress is being made in the energy transition from fossil fuels to ecologically sustainable systems, to the point where many studies support 100% renewable energy.
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New to solar?. This Solar Starter Kit is the perfect kit for someone who wants to begin utilizing solar energy for their off-grid adventures. HQST 100 Watts 12 Volts Polycrystalline Solar Panel, 10 amp PWM Charge Controller, a pair of 20 ft. MC4 Solar Cable (to connect the solar panel and charge controller), and a set of Mounting Z-brackets are all included in this specialized kit.
Whichever setup you select, keep in mind that no two solar setups — just like no two homes — are the same. Even if two homeowners got the same equipment and financing deal from the same company, shadows and geography could create differing solar yields. “People’s usage varies, so their electricity demand varies in their house,” says Kimbis.
Virtually all low-cost inverters are “Modified Sine Wave”. They are usually about 70% efficient, so expect some significant power losses if you are using a Modified Sine Wave Inverter in your system. A Sine Wave Inverter is designed to replicate and even improve the quality of electricity supplied by utility companies. To operate higher-end electronic equipment, a sine wave inverter is recommended.
Still, says Kimbis, as with any major home improvement project, you should get bids from multiple installers and compare the results. The solar company should give you an estimate of how much power that system is going to produce based on annual statistics they know from a variety of different factors: the weather in your region, the angle of your roof, and its ordinal orientation, he says. Those factors will determine the size of the system and how much electricity, on average, it will produce every year.
However, currently each of these energy forms is significantly more expensive than fossil fuels, which will lead to economic dislocations and hardship if they become the only power source for the future.
First-generation technologies are most competitive in locations with abundant resources. Their future use depends on the exploration of the available resource potential, particularly in developing countries, and on overcoming challenges related to the environment and social acceptance.