Block’s Indicator of Sustainable Growth

by Ray Block

Wind energy is the fastest growing renewable energy technology in the world, and its generation quadrupled between 2000 and 2006. Current annual growth is around 30 per cent. The Economist (June 19 2008) says that world wind energy generating capacity will exceed 100 gigawatts (GW) this year.

The US Department of Energy in its Renewable Energy Data Book September 2008 said: “that after a decade of trailing Germany and Spain, the US re-established itself as the world leader in new wind energy. This resurgence is attributed to increasingly supportive policies, growing interest in renewable energy, and continued improvements in wind technology and performance.”

In 2007, Germany remained No1 in world wind capacity, with the US replacing Spain as No2. This year is seeing a complete change about, with the US emerging as No1. The American Wind Energy Association announced on September 4 2008 that US wind energy installations had reached 20.1 GW, with over 7.5 GW new wind capacity to be added this year. West Germany’s generating capacity installed is currently about 23 GW.

In the US, where renewable energy in 2007 represented 14.9 per cent of total energy consumption, (nuclear 8.3%, hydropower 2.4%, non-hydro renewables 4.2%), wind power generating capacity grew 45 per cent last year, with 5.24 megawatts (MW) new capacity installed. Wind power in 2007 represented just over 1 per cent of US electricity supply. Over the seven years 2000-2007, compound annual growth in US wind energy rose 30.7 per cent increasing 6.5 times over the seven year period.

In the DOE’s technical report “20%Wind Energy by 2030” July 2008, the department set out an agenda of how US wind energy could grow to the stage of having 20 per cent of total US energy consumption over the 24 years 2006 to 2030. This would require an installation rate of 16 GW, that is 16,000 MW every year after 2018. That is a very rapid rate of growth. It would involve increasing wind capacity from 16.8 GW in 2007 to more than 300 GW by 2030.

The US has more than 8,000 GW of available land based wind resources that the wind industry estimates can be captured economically. The US Energy Information Administration estimates that US electricity demand will grow by 39 per cent from 2005 to 2030, reaching 5.8 million GW by 2030. The 20 % wind scenario would require delivery of nearly 1.16 million GWh of wind energy in 2030.

Wind energy of this magnitude would allow the displacement of 18 per cent of US coal consumption by 2030, and about 50 per cent of electric utility natural gas consumption. There would be costs involved in wind energy growth, particularly in incremental transmission costs. The market cost of wind energy currently remains higher than that of conventional energy sources in many areas across the country.

As the DOE’s technical scenario suggest, the 20% wind scenario would involve higher initial capital costs to install wind capacity, and associated transmission infrastructure in many areas. But at the same time, it would open the door to lower ongoing energy costs, including maintenance costs.

The Department of Energy says that despite the considerable advances so far made in current turbine capacity, there would be need for considerable further advances, along with enhanced system reliability, and reducing capital costs. Today’s wind turbines currently being installed have three-bladed rotors with diameters of 70 to 80 metres, typically installed in arrays of 30 to 150 machines.

“Drag based devices and simple lift based designs have given way to experimentally designed and tested high lift rotors, many with full span pitch control. Blades that once had been made of sail or sheet metal progressed through wood to advanced fiberglass composites. The direct current alternator gave way to the grid synchronised induction generator, which has now been replaced by variable speed designs employing high speed solid state switches of advanced power electronics.

“Designs moved from mechanical cams and linkages that feathered or furled a machine to high speed digital controls. A 50 kW machine, considered large in 1980, is now dwarfed by the 1.5 to 2.5 MW machines being routinely installed today.”

In 2007, Texas consolidated its position as the leading wind state, followed by California, Minnesota, Iowa and Washington state. Along with Texas’s commitment to spend over the next four to five years US$ 4.93 billion on transmission lines for wind power delivering 18.46 GW of electricity to metropolitan areas of the state, there is a bonanza of new investment in wind power.

Billionaire T Boone Pickens (80 years young) who made his money from oil, but now convinced of Peak Oil, is on a crusade to end US reliance on foreign oil replacing it with renewable energies. Pickens’ current enthusiasm is wind power, his dream in the process of becoming reality is to create the world’s largest wind farm. Location is Nolan County, Texas, housing the largest number of wind turbines in the US. Pickens’ Pampa Wind Project is already spending $2 billion this year on turbines.

The overall plan, which will take four years to complete is to produce 4GW, enough to power one million homes at an all up investment of $10 billion. The wind farm, five times larger than the current largest wind farm, will have 2,700 turbines across 200,000 acres of the Texan panhandle.

Another massive wind farm, this time of 4 GW announced this year is a joint venture between Shell Oil and the largest Texan electricity utility,TXU, which is to be located in Briscoe County.

There remains one critical impediment to the exceptional rate of growth in wind power and solar. The House of Representatives has passed H.R. 6049, the Renewable Energy and Job Creation Act of 2008. This would extend the renewable production tax credits due to expire at the end of 2008. The wind and solar lobbies are saying that failure to extend the renewable energy tax credits will result in the loss of approximately 116,000 jobs-roughly 40,000 jobs in the solar industry and the remaining 76,000 in wind energy.

Whether the Senate passes the House Bill before Congress rises for the November elections is not known at this time of writing.