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THE MONTREAL Protocol to protect the ozone layer will emerge much tougher from a ministerial meeting in London this week than when it was signed three years ago. It is expected to call for the banning, instead of merely the reduction, of many of the chemicals that damage the ozone layer.

A ban will be more expensive than a cut, since it will mean that everyone must replace all of the banned chemicals, which are cheap and in widespread use. Negotiators will need to set up a fund to help developing countries to buy new ozone-safe technology. Without that, developing countries say they will not participate in the protocol.

The critical question is how much it will cost to save the ozone layer. This is especially serious in regard to refrigeration, the area most important to developing countries. Some of the chemical companies who have been deeply involved in the negotiations say it could cost billions. But certain technologies that do not damage the ozone layer could cost a lot less than the expensive new chemicals being put forward by the chemicals industry. For example, researchers are successfully testing cheap hydrocarbons such as butane and propane, already used in aerosols, as refrigerants. In the electronics industry, companies around the world are developing water-based cleaners to cleanse printed circuit boards, another important use of ozone-damaging chemicals.

The emphasis on cost has emerged from the realisation over the past few years that the participation of developing countries is vital if the ozone is to be saved. Last year Michael Prather and Bob Watson, scientists at NASA in the US, calculated that if countries continue to release as little as 5 to 10 per cent of the ozone-destroying chemicals they now emit, the hole in the ozone layer above Antarctica will persist for another century.

There is now little question that the major industrialised countries will eliminate the offending chemicals. But large developing countries could still easily emit enough to maintain the ozone hole. China and India say they will sign the protocol only if they get financial help in meeting its demands.

For developing countries, the difficulty will be in replacing the most widespread ozone destroyers, chlorofluorocarbons (CFCs), which are used to blow plastic foams, clean electronic components, and transport heat in refrigerating equipment.

Refrigeration is the largest and fastest-growing application of CFCs in developing countries. Development Alternatives, a consulting firm in New Delhi, which estimated the cost of applying the protocol for the UN, says 74 per cent of the CFCs in India are used in refrigerators or air conditioners. For most other developing countries, the percentage will be even higher because they have less industrial use of CFCs than India.

The American company Du Pont, which makes a quarter of the world’s CFCs, says it will cost the whole chemicals industry $4 billion over the next 10 years to replace CFCs with safer compounds. The industries that must buy the replacement chemicals will have to foot the bill. Some industries will also have to install new equipment to use them. Du Pont puts the present value of such equipment, soon to be obsolete, at $385 billion. Most of this is for refrigeration.

Cutting replacement costs

Du Pont’s estimate assumes that CFCs will largely be replaced by the new chemicals being developed by Du Pont, the British firm ICI, and others. Like CFCs, these are small halogenated hydrocarbons, but they contain less of the chlorine that destroys ozone. Hydrochlorofluorocarbons, or HCFCs, contain chlorine, but are less stable than CFCs and mostly break down before reaching the ozone layer. Hydrofluorocarbons, or HFCs, have no chlorine.

The new chemicals are expected to cost three to five times as much as CFCs. According to Mostafa Tolba, head of the UN Environment Programme, the chemicals industry finally supported the Montreal protocol in 1987 because it set up a worldwide schedule for phasing out CFCs, which are no longer protected by patents. This provided companies with an equal opportunity to market new, more profitable compounds (New ÐÓ°ÉÔ­´´, 29 October 1988).

For some technologies, however, it is possible to abandon not only CFCs but their relatives as well, and to do so cheaply. The only financial assistance needed will be investment credit to make the change; the substitutes will then pay for themselves. The US Environmental Protection Agency estimates that a company that substitutes CFC propellants in aerosols by cheap hydrocarbons such as butane can save up to $1 million a year for an investment of $50 000 to $750 000.

It is substituting CFC refrigerants that will cost the most for developing countries. A London consulting firm, Metroeconomica, this year assessed the costs of joining the protocol for the UN. It predicts that adherence to the Montreal protocol will be most expensive in the areas of refrigeration, air conditioning and electronics. Refrigeration accounts for 89 per cent of total costs apart from cleaning solvents, which are important in only a few countries such as Korea and Taiwan.

Metroeconomica based its prediction on the assumption that CFC refrigerants will be replaced by HFCs and HCFCs. The US Environmental Protection Agency, the Indian firm Development Alternatives, and the consulting firm McKinsey also estimated the costs of the protocol using this assumption. McKinsey says the extra cost per kilogram of chemicals used as substitutes for CFCs will be six to 15 times as high for domestic refrigeration and automobile air conditioning as for other CFC applications.

These estimates, based on the costs of HCFs and HCFCs, will dominate the debate this week on the amounts of money industrialised nations will have to give developing countries to help them to convert to safer chemicals – a cost put at $995 million by the year 2000 by Metroeconomica.

Negotiators in London will also decide if, and when, to ban HCFC 22, a refrigerant that does some damage to ozone. Du Pont is threatening to freeze its HCFC production plans if early controls on the chemical are imposed in London this week. The company has claimed that if HCFC 22 is banned by the year 2000, as West Germany proposes, developing countries will greatly damage the ozone by continuing to use CFCs, since HFCs will not yet be ready and they will have no cheaper option.

Yet there are alternatives to HFCs and HCFCs, and they are far cheaper. In a laboratory at the South Bank Polytechnic in London, an ordinary refrigerator has been running for six months with no CFCs, and no expensive replacements. Its coolant is cheap propane. In another laboratory in Munich, a refrigerator is running with water as a coolant, and tests show that it could also be more energy efficient than standard refrigerators.

Neither of these cheaper options is being discussed in the debate over the protocol. Engineers working on the technologies say this is because the main negotiators from industry are not experts in refrigeration. They are experts in making the chemicals that have been the focus of concern, and their commercial interests lie with patented HFCs and HCFCs.

John Missenden, head of the Institute of Environmental Engineering at South Bank Polytechnic, claims that it is because of the ‘entrenched attitudes’ of the refrigeration industry that propane is not used as a refrigerant already. Early refrigerators used large quantities of coolant, as much as 11 litres, which made flammable propane a dangerous option. The industry dropped propane in favour of inert CFCs.

Modern refrigerators, however, use only ten millilitres of coolant, about 100 grams. Manufacturers simply ‘have not re-thought the matter of refrigerants’ since volumes diminished, says Missenden. He says propane is a more efficient refrigerant per gram than CFCs. While it is possible for a standard refrigerator to run on propane, a refrigerator designed for propane needs half the coolant, and uses about 10 per cent less energy than one with CFCs.

Leo Manzer, head of CFC replacements for Du Pont, says propane is a problem because it burns. ‘If the coolant leaked near a pilot light, the fridge could blow up and kill a kid,’ he says. Missenden replies that the amount of propane in a refrigerator is the same as in a table-top cigarette lighter. Moreover, he says, refrigerant is sealed into a modern system so firmly that a house fire, for instance, would have to be very fierce to rupture it. Such a fire would also burn CFCs, producing far worse combustion products, such as the nerve gas phosgene, than would propane.

Missenden points out that propane explodes only at concentrations of between 3 and 10 per cent in air. A leak would be unlikely to produce such levels. He says much higher risks of explosion are already tolerated in kitchens. And in a car, half a litre of propane coolant in the air conditioner would be much less risky than the petrol tank, he notes.

The main barrier to the use of propane as a refrigerant is legal. Missenden says that in the US, several gallons of propane fuel can legally be kept indoors in a portable container, but even a small amount in a fixed installation like a refrigerator is subject to ‘the safety precautions required for two-tonne storage tanks’.

The US Underwriter’s Laboratory, which must approve powered appliances in the US, is evaluating propane refrigerants, an indication that some manufacturers are interested. The British standard, written for CFCs, exludes all flammable refrigerants.

Large-scale refrigerating systems use larger volumes of coolant, so propane could be hazardous in these, although oil refineries use propane as a coolant for large industrial processes, such as refining ethylene, says Missenden. He says it would be possible to engineer large systems, such as air conditioning for big buildings, to use propane safely.

Developing countries could profit from the use of propane. CFC refrigerant costs Pounds sterling 5 per kilogram. HFC 134a, its proposed replacement, will cost around Pounds sterling 30 per kilogram. A kilogram of propane costs 50p, is widely available and not patented. Some environmentalists fear that the new HFCs and HCFCs could become standard, however, if the fund to be decided this week is used mainly to subsidise their purchase.

Absorption refrigerators

Hans Haukas, of the Norwegian Institute of Technology, suggests ammonia as a coolant. Equipment using it currently costs more than equipment using CFCs because of the safety precautions needed for ammonia, which can be flammable and toxic. Haukas says that as costs for CFCs rise, ammonia becomes a better option.

Georg Alefeld, a physics professor at the Technical University of Munich, proposes another alternative for small and large-scale refrigerating equipment: a technology already used for minibars in hotel rooms. These make no noise, because they contain no compressor to re-condense the coolant, the step that releases heat in standard refrigerators.

Instead, minibars, along with many Japanese air conditioners and a few domestic refrigerators designed by Electrolux and the Swiss company Sibir, re-condense the coolant on an absorbent chemical. Such ‘absorption’ refrigerators then release the coolant from the absorbent by applying heat, the main input of energy to the system. The released coolant is then evaporated normally to take up heat from the refrigerator’s contents.

The coolant in a home refrigerator would be water, with lithium bromide as an absorbent. Ammonia works in freezers below water’s freezing point, using water instead as the absorbent. There is no reason why CFCs cannot be replaced immediately by absorption systems in water chillers and air conditioners, says Alefeld.

Absorption is cheaper than the use of CFCs or their relatives. It also uses less energy. ‘It is very near the theoretical limits of efficiency,’ says Alefeld. If the input heat is derived from electricity, which in turn was derived from burning fossil fuel, the overall energy efficiency is only about a third that of standard refrigerators run straight off electricity. If fossil fuel is burned directly as a small pilot light in the refrigerator, however, the efficiency is equal.

In research funded by the West German government, Alefeld’s laboratory has now shown that, if waste heat from another machine drives the refrigeration, the combined equipment uses 30 per cent less energy. Dairies or food processing plants, suggests Alefeld, could run their refrigeration off waste heat from other machines. Absorption systems can also pump waste heat to where it is needed.

Japanese and Korean companies have shown interest in Alefeld’s work, but no Europeans so far. An American company, Albers Technologies, has patented an absorption air conditioner, but it is unlikely that American companies will forsake the current coolant, HCFC 22, completely until it is prohibited. The major Japanese electronics firms make large air conditioners with absorption technology, and are developing smaller ones.

Last year the US Department of Energy reported that much refrigeration wastes energy, and estimated that better efficiency could save the US two billion barrels of oil in 20 years. This would reduce emissions of carbon dioxide, the major greenhouse gas. By contrast, HFC 134a, proposed by chemical companies to replace CFC as a refrigerant, is a potent greenhouse gas, several thousand times as potent as carbon dioxide.

None of the alternative refrigerants to HFCs and HCFCs is a patented chemical. It is in no one’s direct commercial interest to promote them as a way of helping developing countries comply with the ozone treaty. It will largely be up to developing countries themselves to spot the cheaper, ozone-friendly alternative. Such technical information, rather than money paid by rich countries to their own industries for new chemicals, may be what really determines the success of the Montreal protocol.