§ 10.16 p.m.
§ Mr. Tarn Dalyell (West Lothian)
I wish to raise the question of a feasibility study for barrages and tidal power. When short-term problems look daunting there is a temptation to desert to the long term, which may appear to be easier. It is my purpose to follow up an undertaking given by the Secretary of State for Trade and Industry on 10th December. I asked the right hon. Gentleman:Whereas it is true that when last looked at, in the middle 1960s, the Solway barrage was economically unattractive, is the Secretary of State aware that some people now seriously think that it might be economically attractive?The Secretary of State replied:I shall look specifically at that scheme to see whether that is so, but my advice is that the barrage schemes available to us could not compete with the nuclear potentiality. Obviously I shall check on this specific scheme."—[OFFICIAL REPORT, 10th December 1973 ; Vol. 866, c. 10.]I followed up that remark and the statement of the Secretary of State for Scotland on 12th December 1973. The right hon. Gentleman said:The situation that we face at the moment is such that any possible new source of energy should be examined."—[OFFICIAL REPORT, 12th December 1973; Vol. 866, c. 406.]It is about 10 years ago to the month that I went, at the suggestion of a previous Conservative Minister, now Lord Errol, accompanied by Dr. Robert Drew, then of Chapelcross, to see Sir William Penney, then Chairman of the Atomic Energy Authority, about the possibility of a Solway barrage scheme combining tidal and nuclear power. Perhaps because we exaggerated our case and perhaps because the relative costs of fuel looked different in 1964 from costs in 1974, we received a fairly stony reply. The purpose of the debate is to start to scrutinise the action which the Government have promised to take and make just two points which suggest that what may have been irrelevant in the epoch of cheap oil deserves a hard, long and cool look today.
158 Within the limit of the time available I shall make general points that would apply either to the Solway or to the Severn. My hon. Friend the Member for Bristol, Central (Mr. Palmer), formerly Chairman of the Select Committee on Science and Technology, has kindly agreed to speak on the special subject of the Severn.
First, progress has been made in France and Russia. Having visited Rance, in Brittany, I am aware that there have been disappointments about electricity output, although the French have 24 10-megawatt units. The Rance problems have been basically those of civil engineering and turbine construction. They do not stem from theoretical reasons against tidal energy. Rance does not rely on the crucial combination of tidal energy and pump storage by nuclear power. The periods of generation are dependent on the tide. That may not necessarily be so in the kind of scheme put forward for the Solway and the Severn. In the same breath I should say that the Government might do well to approach the Russians and talk to them about what they have been doing in Kislaya Bay, on the White Sea.
Secondly, whereas in the past the fundamental difficulty for tidal generation has been the difference between the lunar and the solar cycles, it is now possible on an economic basis to provide complementary pumped storage facilities. For example, development of the Chapelcross nuclear power station site could achieve a rational development by linking tidal output with pumped storage facilities within the Solway area on a low head basis. The multiple use of equipment reduces construction costs, makes additional transmission lines unnecessary and removes the pressure for special inland reservoirs. When one thinks of the difficulties of planning permission that is not a small point.
Unlike a conventional power station, such a combination would produce a steady output throughout the day, regardless of the state of the tide, and calculations show that if 4,000 megawatts of nuclear power were used to drive pumps throughout six and a half hours of low electricity demand at night that station would be able to produce a full 4,000 159 megawatts for the 12-hour daily demand. Therefore, the question of base load can be looked at as a practical proposition.
I come now to my two questions. First, can Lord Rothschild's Think Tank be asked to weigh up the advantages as between a channel tunnel and a major barrage scheme on the Solway or the Severn, given that a barrage scheme of this kind might cost plus or minus £1,000 million? That is a legitimate question for the Think Tank.
Secondly, are the Government prepared to talk about tidal energy at an international level? I realise that any proposal likely to slow down the rate of spin of the earth deserves more consideration than in an Adjournment debate in the British House of Commons, but the serious question is whether there would be a problem of earth spin if several countries embarked upon tidal energy schemes. Would there be any adverse effects on the ocean bed? Do such fears apply at all if there is a two-basin estuary scheme? A great deal more could be said about it. I am limited in time, but I want to show that those who put forward such schemes are aware of the anxieties felt on this score. It would be silly not to express a certain sensitivity towards them.
We are saying, in shorthand, that proposals which in September 1964 or September 1973 would have seemed way out and uneconomic must now come within the orbit of serious consideration.
The argument tonight is not that this country should go hell-bent on tidal energy as some kind of a fad or panacea ; it is rather to extract information and to get the Government to assure the House that the case for tidal energy is not being allowed to go by default.
We warn the Minister in his new Department that he will be plagued by many questions on tidal energy as long as he stays in the Ministry of Energy or until he persuades us that we have no case.
§ 10.24 p.m.
§ Mr. Arthur Palmer (Bristol, Central)
I am obliged to my hon. Friend the Member for West Lothian (Mr. Dalyell) for his usual courtesy in allowing me two or three minutes in which to say a few further words about the possibilities of the Severn tidal barrage. It is a matter 160 of great interest in the West of England, especially in the Bristol area.
There is nothing new about the proposal for a Severn tidal barrage to general electricity. There was a study in 1925 and another in 1945. However, both were for relatively small schemes, with the barrage fairly well up into the mouth of the Severn.
Hitherto, as a power engineer I have accepted the expert judgment that these schemes could not generate electricity at a competitive price. Furthermore, there were serious technical difficulties in taking away energy from a barrage on the Severn in relation to the operation of the national electricity grid.
I tended then to accept the arguments put forward in the past about cost and and about the technical difficulties being hard to overcome. I now believe—and have changed my earlier judgment on the matter, as have a number of other people—that the Severn barrage prospects should be looked at again because of the all-round increase in the price of energy from alternative and—shall we say—normal sources.
I wish to mention a scheme, with which perhaps the Under-Secretary of State for Energy is conversant, recently put forward at Bristol University, suggesting a Severn barrage on a much larger scale than hitherto. The Rance scheme in Brittany, is quite a small one of about 400 megawatts, I think. This latest proposal for a Severn tidal scheme involves the construction of a gigantic barrage from the Weston side of the Channel across to Cardiff ; it would be well down the estuary towards the sea. This is calculated to yield about 4,000 megawatts—roughly the size of four large nuclear, oil-fired or coal-fired power stations.
There is a further new factor in the situation—this applies to the Severn as much as to the Solway—in that it is possible economically to combine nuclear generation, when it ceases to be base-load generation, with the reservoir storage capacity in a tidal power scheme. This would provide for a generally all-round efficient system of generation. I understand that the latest scheme would theoretically give a maximum output throughout a period of almost 24 hours. One of the inherent difficulties about tidal power schemes, unless modified, is 161 that a great block of power could arrive on the electricity system at a most inconvenient time when it was not particularly needed.
I wish to be brief. I conclude by saying that the Select Committee on Science and Technology, through its energy sub-committee, of which I am chairman, is looking at energy resources generally and no doubt we shall deal with tidal energy. In the meantime it will be most helpful to have the Government's up-to-date thinking on this subject as outlined by one of its representatives in the new Department of Energy.
§ 10.28 p.m.
§ The Under-Secretary of State for Energy (Mr. Peter Emery)
I welcome, on the first day of the new Department of Energy, this debate, initiated by the hon. Member for West Lothian (Mr. Dalyell). It allows me to make crystal clear that my new Department is being structured to ensure that every aspect of energy—energy source, energy conversion, energy form and energy need—will be fully considered and properly costed and, where necessary and justified, acted upon.
We have to look with enthusiasm and with an inquiring eye at all these projects—and that goes much wider than the subject broached in this debate. It covers all projects within an entirely new framework embracing the price and supply of oil. That factor brings in an entirely new order. I am aware of the many proposals made for various types of tidal schemes in the United Kingdom, particularly that in the Severn Estuary.
Since my right hon. Friend the Secretary of State for Trade and Industry replied to the hon. Member for West Lothian, we have again looked at the suggestions of the Solway scheme and certain work has been done on re-costing these against the cost of a nuclear power station coming on stream at approximately the same time. Although the investigations which have been carried out have not, because of the time factor involved, been the most detailed, they do not indicate that the scheme would permit the production of electricity at any favourable comparable cost with nuclear power generation.
None the less, I am aware that the proposal to use the Severn as a combined tidal source and pumped storage site is 162 well advocated. It has been pointed out that the pumped storage application will be of particular importance when nuclear power stations come off the base-load operation. However, even the most optimistic of us cannot expect this to happen much before the latter part of the 1980s. This shows the time scale available in having to reach decisions on this type of energy scheme. All possible new sources of energy must be looked at again in the light of the change in the oil situation which has arisen over the last few months.
1 must stress a number of factors which could change in the coming years and which must be borne in mind in considering the possibilities of the use of tidal power. New uses may be found for what is now known as off-peak electricity and the date at which nuclear comes off base load may be later even than I have projected. I am thinking here of the possible development of electric cars and of the increased use of domestic off-peak heating. Even if off-peak nuclear energy does become available, there are alternative methods of storing the electrical energy. There is the present method of using high head pumped storage schemes, and the potential for this type of energy storage is not yet exhausted, although there are not many more sites. There are more futuristic proposals such as the production of hydrogen and the storage of compressed air underground. All of these other alternatives have their attractions and their drawbacks. It is of the utmost importance that we do not allow short-term difficulties to cloud our judgment on much longer-term issues.
In response to the question put to me about the international aspect of the use of tidal power, I can say that we have had discussions with the Canadian officials and are dealing with the Canadian assessment of tidal power. My Department has examined the Rance scheme in France. We have made approaches to the Russians, but there are some difficulties here, in that the economic analysis of the Russians is very different from our own. None the less, we have gone forward in attempting to judge the capabilities of projected schemes by the Russians.
§ Mr. Dalyell
In relation to the Canadians, Lorne Gray is coming here 163 shortly. Will barrage schemes be on the agenda, particularly in connection with Candu reactors, or possible joint British-Canadian co-operation on heavy water steam generating reactors?
§ Mr. Emery
Discussions are based on the nuclear side, but if it were thought worth while to project this concept in conjunction with anything that the Canadians wanted to put to the Government, we should be most willing to listen to anything they had to say.
An appraisal of these vast multi-barrage schemes is not easy. Tidal power schemes are particularly so, because, unless expensive measures are taken to prevent it, the availability of power from them drifts continuously in an out of phase with the hourly demand for electricity. This peculiarity imposes great uncertainty about the annual total value to be placed on the electricity output and on the assessment of that output.
The valuation of the other benefits is equally difficult, as is the costing of the barrage and the assessment of the risk of the barrage. None the less, what I am trying to stress is that there is a new ball game in this matter, and my Department is convinced that we must not let any possible scheme fall because it has not been properly looked at and considered.
I think that successive Governments have examined the three main types of barrage proposal and have concluded that because of the cost facts and the benefits and risks involved the case for proceeding with a barrage is not sufficiently strong. There is a large measure of judgment in this, and therefore a definite answer could not be given without the use of large resources to make these assessments.
The total output from the tidal stations in the United Kingdom might be the equivalent of about 20 per cent. of our present electricity demand. It would help, but it is not the answer to our energy needs. We must in the future depend, I believe, on nuclear power, and it is the Government's policy to press ahead as rapidly as possible with the exploitation of nuclear power. It 164 would be wrong to divert any of the necessary speed and pressure away from the exploitation of nuclear energy for the generation of electricity.
The latest assessment of the position of tidal power made by the Government towards the end of last year and the conclusions reached were that electricity produced from a tidal power scheme would cost about two and a half times as much as electricity generated in an advanced nuclear reactor. The electricity boards share our views about the prospects of tidal power.
§ Mr. Dalyell
It might be unreasonable to ask for an off-the-cuff answer, and perhaps the hon. Gentleman can write to me about this. Can the Minister say whether, in the cost calculations, such factors as the eventual death of the nuclear power stations and the relative pollution-free use of barrages have been taken into consideration? The basis of calculation is very important, because the dismantling of nuclear stations after 30 to 40 years would be brought into the cost factor.
§ Mr. Emery
I was talking about the major objections to them, one of which is that they take water away from parts of estuaries. I did not want to get into that, because that is not the level of discussion that we are having.
We shall continue to keep this type of matter under review, I hope with the help of the CEGB, which I want to ensure is investigating this matter as much as we are. Its responsibility is to provide an efficient and economic supply of electricity, and if any new way can be found of doing so, we want to encourage it.
§ Question put and agreed to.
§ Adjourned accordingly at twenty minutes to Eleven o'clock.