Independent: The relationship between energy and the environment will be one of the defining issues of the 21st Century. Climate change has led to growing calls for action to be taken to halt it. The most recent major effort was last year's global Climate Change Conference in Paris. There, world leaders agreed to reduce emissions to stop global temperatures rising by 2 degrees centigrade, an ambitious target given current trends. Ireland pledged to do its bit by slashing greenhouse gases by at least 40pc by 2030,...