New energy sources

New energy sources

Gas hydrates

A report from the Science Festival organised by the British Association for the Advancement of Science, says that vast fields of gas crystals discovered on theseabed could be the new fuel for the next century. Researchers said that the reserves of crystals, called gas hydrates, dwarfed those of coal, oil and natural gas. Dr Ben Clennell of the UK's Leeds University's School of Earth Sciences said that:

A conservative estimate is that there is enough gas locked away in these ice-like hydrates to double all known fossil fuel resources of the earth ... that have been used or ever will be.

Japanese initiatives

Japanese scientists are to try to extract gas hydrates from beneath the sea floor. The frozen methane bound up with ice in undersea mud could supply, they claim, the planet's needs for two centuries if a way can be found to overcome the technical problems of accessing them. It is also reported that India is particularly interested in extracting the gas hydrates as it does not have accessible oil or gas reserves.

Japan too is reliant on imports of oil and is starting its own multi-million pound pilot scheme next year (1999) to test the technology needed to mine the crystals. The crystals are to be found at depths of 500-3,000 metres.

Ocean drilling programme

In the USA some £60 million was being spent on research into gas hydrates and, in addition, big reserves are said to have been found off Norway. Britain, it is thought, was likely to have deposits in the Atlantic, west of Shetland.

The potential of gas hydrates is such that the ocean drilling programme, a grouping of scientists from 30 countries, funded in the UK by the Natural Environment Research Council, is investigating sediments, rocks and muds holding clues to past climates and the evolution of the Earth.

The crystals are said to be formed from natural gas at low temperatures and high pressures. Conventional resources of natural gas are formed from heat inside the earth. But the gas hydrates are formed from gaseous emissions of marine bacteria trapped in ice crystal structures a few metres below the ocean bed on the continental margins. Dr Chennel said that the condition that formed the gas hydrates covered "millions of square kilometres of seabed in both high and low latitudes, including much of the continental slopes of the North Atlantic".

It was also reported that energy companies were currently studying ways of extracting the gas. These include the method of firing hot water or de-icing agents down drilling equipment. The conseqences of using such methods may not please environmentalists since the sea beds were the home to bacteria and worms at the base of the food chain. The dangers of accelerating global warming, tidal waves being triggered by the risks of vast undersea mud slides, have also to be examined.

The potential gain from using such a vast resource cannot be ignored and once again the apparent dangers of extracting the gas have to be carefully considered against the damage to the environment. As Dr Clennell said at the Science Festival lecture, the discovery of hydrate reserves was not entirely cause for celebration.