Reuters: At the age of 25, Dan Lewer is going into retirement — carbon emissions retirement that is. Lewer is co-founder of a new online carbon offset company called Carbon Retirement (www.carbonretirement.com), which launched on July 15. Carbon Retirement offers consumers and companies a novel approach to offsetting their carbon footprint by letting them dip into the European Union’s Emissions Trading Scheme, the 27-nation bloc’s flagship weapon in fighting climate change. Now …