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Showing posts from May, 2009

Renewables Global Status Report - and Funding and Sharing Request

I thought you might all be interested in the latest status about renewable energy worldwide.

Please see the REN21 Renewables Global Status Report: Energy Transformation Continues Despite Economic Slowdown. See

Here are some of the facts:
* Global power capacity from new renewable energy (RE) sources (excluding large hydro) reached 280,000 MW (280 GW) in 2008 - a 16% rise from 2007 and three times the capacity of the United States nuclear sector
* 73 countries now have RE policies
* the US will invest over $150 billion over 10 years in RE
* RE investment in 2008 was $120 billion, up 16% over 2007
* Wind energy capacity grew by 29% in 2008 to reach 121 GW. (South Africa's total electricity capacity is 44 GW.)
* Grid-connected solar PV grew at 70% to reach 13GW
* Solar hot water in Germany (which has less sun than South Africa) set record growth in 2008, with over 200,000 systems installed. (South Africa installed a few hundred in 2007)
* By …

Part 8: Renewable Energy System Design - "DIY Sizing"

Let's get around to looking at some calculations. I suggest that you sit down with a piece of paper and a pen so that you can work through this example with me.

The problem:
During a 4 hour Eskom power failure, you want to run your computer for 4 hours and it uses 300 Watts (per hour); you also want to run 4 lights for 4 hours. Each light draws 8 Watts. You don't want to use a noisy, smelly and pollution generating generator. You want to build a system yourself and one day add a solar panel or solar array to it. You are prepared to spend a bit extra to make that "start" in Renewable Energy.

Renewable Energy "Thinking" Notes: Eskom energy is still much cheaper than generator energy, so we'll start with charging the battery using Eskom energy. Eskom energy isn't clean, but we need a starting point. We can add solar and other technologies to this system later. My Eskom energy (electricity) at the moment is about 70 cents per kwh. This in May 2009…