Solar energy saves money on electric bills, and it also helps our power grid. On August 14, 2003, too many people were using electricity because it was a hot day. Suddenly, all the power went out across the Northeast United States and Canada, and 55 million people were suddenly in the dark! In New York City, people had to walk miles across bridges to get home because there were no trains or subways running. It was an expensive incident for the government and industry. But if we use more solar energy, we will put less pressure on the power grid. That means fewer blackouts.

What kind of evidence does the author use to support the claim that solar energy helps the power grid?

anecdotal
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statistical
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