Professor Tony Trewavas: Go nuclear '“ renewables are not the way to cut carbon and maintain quality of life

Professor Emeritus Tony Trewavas, Scientific Alliance

There is enormous momentum behind present climate policy because of the political and scientific capital sunk into it. Yes; climate temperature has risen for about the last century. Yes; atmospheric CO2 has increased certainly from the 1960s onwards. Yes; CO2 is a greenhouse gas.

The Intergovernmental Panel on Climate Change is charged with assessing future temperatures. If CO2 doubles by the end of this century, then climate temperature (assessed from around 70 separate models) is projected to increase between 1.5-4.5C. Projections are not predictions, however. Recently, climate scientists have indicated present models run too hot, suggesting the lower end of temperatures could be more likely.

Models are limited by climate understanding and the quality of information used to construct them. Climate is an open, irreducibly-complex system with many poorly understood feedback effects.

Attempts at predicting the far-off future simply transfer present knowledge but with one additional element; in this case elevated CO2. We can only guess at population numbers 100 years hence, what transport will be used, the world’s economic activity, the state of forests, oceans or what unpredictable technology we will have developed, particularly for energy generation. All influence climate.

Technology and innovation are developing exponentially; the more you know, the easier it is to discover new things. With a digital world, positive feedback in discovery and innovation is inevitable. These unknowables make any attempt at temperature prediction uncertain.

However, a climate policy that states at the outset that its priority is the quality of human life is both positive and inspirational. Policy that centres on emissions reduction tends to have unforeseen consequences.

Diesel engines were lauded because emissions were lower. But they also generate health-damaging particulates that contribute to the production of black carbon (soot). Phasing them out will be expensive. Black carbon forms from incomplete combustion of fossil fuels, biomass and biofuels and is probably responsible for current arctic ice melt concerns. One ton of black carbon is equivalent to 600 tons of CO2 in warming terms.

Poor urban air quality is exacerbated by carbon monoxide, nitrogen oxides, methane and other volatiles which interact to generate toxic ozone, generates crop losses estimated to be £10-20 billion annually and increases warming. Strict and enforceable regulation would improve health and cut emissions.

It was assumed by government that burning wood in power stations would reduce emissions compared to coal. As a consequence, DRAX, our largest power station, was converted at considerable expense to burn wood. In fact, the reverse is the case. A quality of life scenario would show that burning wood generates particulates and produces much more toxic volatiles than coal; that mankind has disadvantageously reduced forests worldwide by 20 per cent, that leaving trees in the ground and saving associated wildlife is better than incineration.

Cutting down forests to burn sets a poor example for tropical conservation that is vital to humanity’s future. Prioritising emissions constraint or mitigation for poor countries with large populations paints a picture of rich countries attempting to foist limits on them and prevent economic development to enrich their populace.

A commitment to a secure, stable and low cost supply of electricity with a price below that of coal is surely basic to a climate policy based on quality of life.

For large-population countries, nuclear power can fill these requirements but the industry needs to prioritise waste and safety and invest in fail-safe, liquid salt reactors using thorium that negate long-term waste issues.

Renewables are popular but parasitic on a stable electricity supply. Charges for intermittency need to be introduced to show that renewables on their own currently fail on the requirement of low cost.

Adaptation is essential to defend the quality of human life. Adaptation is not mitigation. Proactive policies and foresight are needed to ensure resilience in the face of uncertain and sometimes devastating change. A secure and reliable electricity supply and cheap energy production is fundamental. Scottish government policies fail on this issue.

Professor Emeritus Tony Trewavas, Scientific Alliance.