Is energy efficiency really cheaper than switching to renewable energy sources as a way of cutting carbon emissions?

Let’s face it: energy efficiency is boring when compared to the (relative) excitement of developing new sources of low-carbon electricity or heat. The popular science magazines are full of articles on new forms of solar panel and the latest designs for wind turbines. Improving the insulation of ordinary homes, shifting to LED lighting or increasing the take-up of heat pumps rarely command the attention of editors.

Read More

Republic of Maldives: a plan for carbon neutrality

The Maldives will be the first country to be overwhelmed by the effect of climate change. The republic is a collection of coral atolls with maximum heights of one or two metres above sea level. Climate change is increasing worldwide sea levels and the atolls will probably go underwater by the end of the century. The 300,000-400,000 people who live on the Maldives are not responsible for global warming. Their emissions per head (even including aviation fuels for incoming international tourism) are less than a seventh of typical European levels.

Many countries have set ambitious targets for the reduction of carbon emissions. The government of the Maldives seeks to encourage this trend by going one step further with a plan for near carbon neutrality within ten years.

This is an immensely challenging target. Chris Goodall (author of this blog) and Mark Lynas, the prize-winning climate change author, were asked to provide a short outline of how it might be achieved and what it might cost.

In the rest of this note, we show our calculations. We will be the first to acknowledge that this work is incomplete. Although it was tempting to conduct fieldwork in some of the most attractive island resorts, we did our analysis using publicly available information and with help from officials attached to the Maldives government.

Our work shows that near neutrality is possible, but expensive. It will take at least $1.1bn for this small island state. The Maldives imports almost all its fuels in the form of refined oil products. Rates of financial return to the investment therefore depend largely on the price of oil. If expectations of future oil prices exceed $100 a barrel, we judge that the plan is sufficiently attractive to be financeable by international institutions such as the World Bank.

Comments on this work will be very gratefully received.

Read More

Why do global land use patterns matter so much?

George Monbiot rightly observes that the earth's resources of biomass are limited and cannot be simultaneously claimed for multiple uses: liquid biofuels, fuel for heating, biogas, and biochar. This presentation looks at the globe's land and biomass production to assess how much space can be given over to non-food uses and how much energy this can generate. This is one of the crucial questions facing the world: how much energy can we use from biomass before this affects the ability of the world to provide enough food for nearly 7bn people, rising to at least 9bn by 2050?

Read More

Are biofuels responsible for the sharp spikes in food costs?

The world has decided that much of the blame for the rising cost of foods can be ascribed to the use of grains for biofuels. The case for the prosecution is simply made. About one hundred million tonnes of maize from this year’s US crop will be diverted into ethanol refineries, an increase of a third on 2007’s figure. The maize used for ethanol represents almost 5% of global production of all types of grain. One in twenty cereal grains produced in the world this year will end up in the petrol tank of US cars. Other countries are also pushing ethanol, but the US has moved most aggressively to increase the use of food for fuel.

Read More

More bad news for the poor

Two pieces of news from Tuesday 26 February. A UK investment fund is trying to raise £330m to build two large biofuels plants on the eastern coast of England. And the price of wheat rises to a new high of over $12 per US bushel in Minneapolis (over £220 per tonne) as worldwide shortages force prices ever upwards.

Read More

The promise of cellulosic biofuels

Switchgrass biofuel crop
Switchgrass biofuel crop

Will next-generation biofuels have a less destructive effect on agriculture? A study just published by US government scientists suggests that so-called ‘cellulosic’ ethanol has much better energy balance than today’s biofuels.[1] By energy balance, we mean the energy used to make the fuel compared to its energy value when burnt in a car’s engine. News summaries of the paper’s contents focused on one estimate that suggested that to make cellulosic biofuels might only need 6% of the energy value contained in the fuel. Depending on which crop is used, where it is grown, and how it is refined, most of today’s biofuels have only a weakly positive energy balance. So the paper gives hope that we might expect considerable progress towards carbon-neutral transport fuels when we can start refining all vegetable matter, not just foodstuffs, into fuels.

Cellulosic biofuels may well become important sources of motor fuels. There is certainly huge amounts of money flowing into the field. Unfortunately none of the news articles covering the US research pointed out the technology for turning cellulose into fuel is still a long way from commercial viability. Yes, we can turn grass into ethanol, but at prices which will double the price of petrol. And the greenhouse gas savings will almost certainly not be as attractive as the paper suggests, not least because the authors did not include the serious impact of nitrous oxide emissions from fertilised fields.

Read More