While homes can probably be designed and built that can function without electrical input at night and still have light, computers, and sound systems, there are plenty of electrical uses that actually need a reliable and continuous source of power. Storage is a prime need to make solar truly work.
Global Solar Consumption Is Going ExponentialGregor MacDonald, Gregor.us | Jun. 18, 2012
From a very small base, and from a tiny position in world energy supply, the buildout of global solar power is starting to go exponential. Last year, according to the just released BP Statistical Review (you must access the Excel workbook for solar data), global solar generation nearly doubled to reach 55.7 TWh (terrawatt hours).
To put this power capacity in context, North America generated almost 100 times as much power in 2011 from all sources (coal, natural gas, hydro, nuclear, wind, solar), to reach 5204.5 TWh. By that measure, solar power capacity on a global basis can barely be detected, and is therefore a kind of joke, right? Uhm no, that would be wrong.
As world nuclear power goes into retreat, because of its enormous expense, catastrophe-risk, and complexity, it is power generated by solar that offers easy time-to-completion benefits and project clarity, especially in the developing world. (Indeed, nuclear power again lost primary energy share last year, according to the BP Statistical Review). Moreover, as the world is no longer able to fund economic growth with oil, owing to flat global supply, the industrial economy continues to migrate towards the electrical grid. While this certainly means that coal fired power generation will dominate for the next decade, it’s also the case that a more robust powergrid will become the receptacle for solar power. more
Living in the middle of a large continent, a discussion of the tides is almost as distant and abstract as a discussion of the atmosphere of Venus. Which is probably why I find it interesting. I especially enjoy the idea that Norway is investing in tidal electrical generation. Norway may be an oil power these days but she was already heavily invested in renewables (esp. waterpower) before anyone found oil. She views oil as temporary wealth—riches that should be spent increasing the supply of her renewable energy.
Lack of storage options challenges green energy sectorDW 19.06.2012
Many renewable sources of power, such as wind and solar, cannot provide steady energy output. New storage options would solve one of renewable energy’s greatest challenges.
Energy providers around the world are scrambling to develop storage for renewable energy in order to secure availability and improve profits. Supplies of wind and solar power fluctuate depending on the weather.
"A storage unit helps to ensure a steady flow of energy from wind and sun, making it easier to respond to demand," said Martin Kleimaier of Germany's Association for Electrical, Electronic and Information Technologies (VDE). Last year, energy from sources like wind, biomass, hydroelectric plants, solar panels and waste incineration covered 20 percent of demand in Germany.
By 2050, Germany - which has the largest population of any EU country - is expected to draw as much as 80 percent of its power from green energy sources. That means new storage systems are needed to ensure reliability.
There are a number of new storage ideas already on the table. "There won't be one solution to for everything," said Claudia Kunz of the German Renewable Energy Agency. "There is a difference between short-term and long-term storage," Kunz explained. "Short-term storage unit capacity ranges from seconds and minutes up to a few hours. Long-term units can provide energy for weeks and months."
One solution is the pumped storage hydroelectric power station. These are short-term storage plants used primarily in mountainous regions. If there is excess electricity from wind or solar generation in the grid, it can be used to pump water from the valley, up the mountain to a subsidiary dam. When the water runs down the pipes again, it turns the turbine which is connected to a generator to produce electricity. The water isn't released until demand increases, so power facilities aren't as vulnerable to energy shortages caused by fluctuating supply and demand.
But a lot of energy - as much as one third - is lost as the water is pumped upwards. In Germany, pumped storage power plants need 7,500 megawatts of energy to run, which leaves the network with only four to eight hours of available power.
Researchers see chemical storage as a good solution for long-term energy storage. Jürgen Schmid of the Frauenhofer Institute for Wind Energy (IWES) in Germany explained that this system converts excess electricity into combustible gases. For example, wind tubines generate power. If there is too little demand for that power when the wind is blowing, the energy produced is used to split water into hydrogen and oxygen. The hydrogen is stored and used later to generate electricity. This releases no harmful emmissions and the only byproduct is water.
Hydrogen and methane are considered top choices for large scale energy storage. But, depending on how these gases are processed determines the size of their carbon footprint. Research is continuing as hydrogen storage is still considered largely inefficient.
Availability of storage grids presents another challenge for energy providers. VDE's Wolfram Welßow told DW that expanding the electricity grid is a top priority in Germany.
Claudia Kunz of the German Renewable Energy Agency also wants to see the network infrastructure expanded as quickly as possible. But she says there are challenges ahead. "An enormous amount of research needs to be done in order to develop energy storage systems. A lot needs to be done to make them cost-effective," she said.
Experts say politicians should create a framework for use, so that the energy storage units can go online as soon as they are available. The German Environment Ministry expects demand for storage units to jump sometime between 2020 and 2030. more
Welcome To Norway: The Country That Gets Power From THE MOONRob Wile | Jun. 18, 2012
We recently took a big gulp of data from BP's annual Statistical Energy Review, released last week. and determined which countries get the greatest amount of energy from which resources.
One country's ratio instantly stood out: Norway.
It turns out that the Scandinavian country best-known as one of the largest oil exporters in the West (12 percent) gets nearly two-thirds of its energy from hydro power — 63%!
At first we pictured everyone riding around in paddle boats. But after doing some research, it got even stranger:
The country is a huge producer of tidal power.
The movement of tides, if you'll remember from elementary school science class, is caused by the moon's gravitational pull.
Which means Norway gets its power from the moon!
In 2003, the country built the world's first commercial natural tidal plant. Seven years later, it opened the first floating tidal plant.
Exact data showing total share from tidal power for the country is a bit fuzzy.
But it's clear they aren't letting up — they recently announced construction of another plant prototype in March. more