There is no doubt at all that it will be impossible to meet our CO2 emissions targets unless we also do much more on energy efficiency. My hon. Friend will know of the very strict new regulations on energy efficiency for the building of new homes. Work is being done by the Carbon Trust and others, and obviously there are plans to switch to low-energy light bulbs and so on that are immensely important. One fact that shows the significance of small changes is the fact that if every home had at least three low-energy light bulbs, it would save the amount of energy used for the whole country's street lighting, so there is a massive amount that we can do. Again, over the next few weeks, we will announce further proposals on that issue.