100% renewables by 2020 is possible

We all know about the government and big business's so-called "solutions" to the climate change crisis: "clean" coal, carbon trading schemes, etc. But what are some real world solutions to the climate crisis and what real action is being taken?

Modern forms of renewable energy such as wind and solar thermal are proven to be able to supply large amounts of baseload electricity. Renewables are not some "hippy fantasy".

For example, bigger wind turbines have now been developed (mostly in Europe) that are able to access the better airflow at greater heights and produce more power, more reliably.

Wind turbines have doubled in size in the past decade. The hub, or generator, on modern wind turbines such as the E-126 sits 100 metres off the ground, the blades have a diameter of 126 metres, and one turbine will produce, on average, two megawatts (MW) of electricity, enough to power thousands of homes.

A 2007 Stanford University study showed that suitably located, linked wind farms will never produce less than 30% of their capacity. So the rule of thumb is that about 3MW of wind power is needed for every 1MW of coal we want to replace.

For a big coal-fired power station like Bayswater in New South Wales (3000MW), we would need to build 9000MW of wind farms, about 1500 turbines.

Wind is one of the cheapest forms of renewable energy, costing about $1.2 million per megawatt capacity.

Solar thermal power uses big fields of mirrors to concentrate the heat of the sun onto pipes filled with oil. The hot oil is used to boil water and the steam produced runs a turbine.

Most of Australia's electricity is made by burning coal to produce steam to run turbines, yet there are many sunny areas where using the heat of the sun could replace the burning of coal.

Furthermore, a new solar thermal plant in Spain called Andasol 2 is also able to store heat and can produce electricity for seven hours after sunset. Molten salt in giant vats absorbs heat from the plant during the day, which can then be "dispatched" when needed.

Apart from wind and solar thermal, there are also solar panels (photovoltaics) and bioelectricity. Bioelectricity is made by burning waste from crops such as sugar cane and corn.

It would be silly to grow crops (or worse, to cut down forests to plant crops) just to burn them, but a lot of farmers worldwide simply burn their crop waste out in the field and the energy is wasted.

Between wind, solar thermal, photovoltaics and bioelectricity, there is the potential to meet all of our electricity needs through renewables by 2020. What is missing is the political will to make it happen. That's where the climate emergency movement comes in.

From GLW issue 797