My Lords, why are we to assume that greater energy efficiency in the home will only happen if we invest in renewable energy? We will be able to invest in greater efficiency in the home later anyway. The idea that we will get more efficiency in the home because we invest in renewable energy has never seemed very sensible. As for the cost of renewables towards energy prices, we can agree or disagree about the figures but it depends on your assumptions about what will happen to wholesale gas prices.
What have we achieved with the £2.9 billion we are spending this year on subsidies to renewable energy? We produced about 1% of our total energy from wind and solar this year. If you take total energy—including transport, fuel and everything else—wind provides only about 1% of the energy we use in this country. After accounting for the back-up—wind needs about 80% back-up to make sure that energy is available when it is not blowing—we have cut our carbon emissions through the use of wind and solar by probably less than 0.5%. That is surely a very small return on our investment.
All we are really doing is driving carbon emissions abroad, as has already been mentioned. Professor Dieter Helm, who has also been mentioned, said that carbon production in Britain fell by 15% while consumption rose by 20% between 1990 and 2005. We are consuming the carbon, it is just that somebody else is producing it. As Professor Helm also said, if we follow the Leader of the Opposition’s proposal and decarbonise altogether by 2030, “we may actually make global emissions higher than they would otherwise have been” because of this effect. Unilateral decarbonisation is like building a flood bank at the end of your garden when your neighbour does not.
The noble Lord, Lord May, challenged me on the point about climate change. We have heard that the position on climate change has become more certain. Those who have come to that conclusion are obviously reading a different Intergovernmental Panel on Climate Change Summary for Policymakers than I am. The one I saw said that it is now 95% sure that more than half the warming since 1951 is man-made. That is a slightly weaker statement expressed slightly more strongly than six years ago, and a statement about the past not the future.
In what the Intergovernmental Panel on Climate Change says in its latest report about the future, you find more uncertainty than six years ago. Let me give
nine separate examples of ways in which the Intergovernmental Panel on Climate Change has retreated to a slightly less alarming and less certain position than six years ago. First, it acknowledges the pause or standstill in temperature for the first time, which has taken place for either 15 or 17 years depending on whether you look at surface or satellite temperatures.
Secondly, it acknowledges for the first time since its report in 1990 that the medieval warm period was at least as warm as today on a global level and therefore that today’s temperatures are not unprecedented in the last thousand years. Thirdly, it acknowledges for the first time that Antarctic sea ice is slowly expanding not retreating, which was not predicted by its models. Fourthly, it acknowledges that 111 of its 114 models overstated warming in the last 15 years.
Fifthly, it acknowledges that the range of equilibrium climate sensitivity is lower than it was six years ago. It says that it cannot now give a central estimate, whereas six years ago it gave a best estimate. Why can it not do that? The average of 16 separate estimates of that quantity made by empirical studies since 2011 is 60% cooler than the ECS that was assumed in the IPCC models. The noble Lord, Lord May, says that it is important to make a calculation of how much carbon we must produce by the middle of the century, but that depends upon your estimate of equilibrium climate sensitivity. If it turns out that it is as low as the range is now suggesting, and as the latest studies suggest, that changes the calculation entirely.
The sixth thing that the IPCC acknowledges is that transient climate response is lower. That is the more immediate policy-relevant number because it tells you how much warming actually happens by a particular point in the future rather than what takes a lot longer later. Seventhly, it acknowledges that sea-level rise, which is definitely happening, is lower than some authorities, such as Professor Rahmstorf, have tried to persuade us that it is. Eighthly, it says, using the words “very unlikely”, which it specifically defines in statistical terms, that a collapse of the Gulf Stream is very unlikely, that a collapse of the west Antarctic or Greenland ice sheet is very unlikely and that an explosion of methane from clathrates on the ocean floor is very unlikely.
Ninthly, it says that it has low confidence in a number of tipping points that were previously thought to be possible concerns: the collapse of tropical forests, of boreal forests and of the monsoon, an explosion of greenhouse gases from the Arctic permafrost and an increase in megadroughts. It says that it has low confidence in these things. These are major retreats. We know that the harm being done by climate change will arrive considerably later in this century. There is the harm being done now by decarbonisation policies: biofuels driving people into poverty, and wind costs driving up people’s energy bills and causing them trouble in heating their homes.
These problems are arising now and we are being dangerously close to callous if with higher energy costs we tighten even more the noose around the necks of needy people in this country. This week the Minister President of North Rhine-Westphalia, Hannelore Kraft of the Social Democratic Party in Germany, has said that she thinks we should slow down this transition to renewables until we are more certain.