Internet search giant Google says that it consumed about 2.26 billion kilowatt hours of electricity last year, equal to the energy used in 200,000 homes. But while that represents an enormous amount of energy, Google says the services supported by its expanding data centers reduce energy use globally and allow users to improve their own energy efficiency. In its official blog, the company said the typical user of Google’s products — including search, Gmail, and YouTube — uses about 180 watt-hours monthly accessing those services, or less than “a light left on for three hours.” It’s the first time Google has shared information on its energy use and greenhouse gas emissions, an attempt to be more transparent as it expands its data center operations worldwide — including a new center in Finland — and promotes its cloud-based data services. The company also disclosed that it emitted about 1.46 million metric tons of carbon dioxide in 2010, but said that about one-quarter of its electricity came from renewable energy sources. The company also buys carbon offsets for its emissions.