In a speech he made earlier today (highlight clip above) in Washington, D. C., Al Gore challenged America to “end our reliance on carbon-based fuels.” Mr. Gore contends that our over-reliance on carbon-based fuel is at the core of our three biggest challenges today: the economy, the environment and national security.

“We’re borrowing money from China to buy oil from the Persian Gulf to burn it in ways that destroy the planet. Every bit of that’s got to change.”

The former vice president alludes to some of the potential solutions with the following factoids:

• Enough solar energy reaches the earth every 40 minutes to supply 100% of the worlds energy needs for a year.
• Enough wind blows through the Midwest corridor to supply 100% of the US energy needs.
• Geothermal is another relatively underutilized source of energy.

Mr. Gore’s ultimate challenge was this:

“Today I challenge our nation to commit to producing 100 percent of our electricity from renewable energy and truly clean carbon-free sources within 10 years.”

He likened this challenge to Kennedy’s challenge to land a man on the moon and return him safely in 10 years. Mr. Gore makes reference to falling prices of the specialized silicon for solar cells, the continuing performance increases in the semiconductor industry and the rising prices of oil as indicators that now is the time when we can meet a challenge such as this. Mr. Gore also notes some of the obstacles to reaching this goal, such as the need for a Unified National Grid for power distribution and a switch to an all electric vehicle fleet. He also stresses the need for an increased commitment to efficiency and conservation.

The speech includes some specific steps to get us moving in the the right direction. One of his key objectives is to sharply reduce payroll taxes and start taxing carbon emissions. Mr. Gore summed this up with “tax what we burn, not what we earn.” Another objective is for the US to rejoin the global community and lead efforts to secure an international treaty to cap CO₂ emissions.

Personally, I think this is the call to arms we really need to get moving. Unfortunately, unlike JFK in the 60’s, Mr. Gore is not the President of the United States of America. It remains to be seen what sort of influence this former VP and noble prize winner will have on the next administration. Will anyone running for the presidency or any of the top offices in the Congress be bold enough to take up this challenge?

“We must now lift our nation to reach another goal that will change history. Our entire civilization depends upon us now embarking on a new journey of exploration and discovery. Our success depends on our willingness as a people to undertake this journey and to complete it within 10 years. Once again, we have an opportunity to take a giant leap for humankind.”

For more information, join the WE campaign at wecansolveit.org. You can find the text of the full speech here.

Wind is a fairly abundant, widely distributed potential source of clean energy. Most commonly it is harnessed by a wind turbine and converted to electricity. It is estimated that wind power could account for as much as 72 TW of energy world wide, though it accounts for less than 1% of current electricity generation. Some countries manage to produce significantly more, such as Denmark which generates nearly 20% of their nationwide energy from wind.

While wind has wider distribution and better availability throughout the day compared with solar, it is intermittent. Typical wind farms generate energy at about 20-40% of their theoretical maximum output. The ratio of actual production to the theoretical max is called the capacity factor. For example, a 1 MW wind turbine with a 35% capacity factor will produce 0.35 MW on average. This still leaves the need for either overproducing and storing energy during peak product or reverting to an alternative energy source during low wind periods.

In addition to intermittency, there are some environmental concerns for wind power. While no greenhouse gases are emitted during the operation of wind turbines, there is some concern that due to the intermittent nature of wind generation, the quick-start back up generators may be more polluting than the standard fossil-fuel plant they are replacing. Also, wind farms require large, unobstructed areas of land. There is also a concern that these wind farms have a negative impact on wildlife, especially birds and bats. While some studies have shown significant impact to bat populations in especially sensitive areas, most studies show that the impact on birds is fairly negligible. Another potential concern is whether noise produced by wind towers at sea could pose a risk to ocean mammals.

It doesn’t seem likely to me that wind can solve all of our energy generation needs. It does seems like a good complement to other alternative energy sources. Perhaps a combination of well placed wind farms and solar farms could meet most of the world’s energy needs. It seems like we would still need to make some major improvements in energy storage and transmission for this to come about. I certainly hope we will all start to feel the winds of change…