In this article I want to sound a note of caution. As I underlined in my editorial, the world faces a crisis, the worst crisis in human history. And as I emphasised, new technologies are the best hope we have in terms of slowing and then reversing global warming. All over the world, in science labs and universities, in engineering companies and architects’ offices, the smartest and most imaginative people will be thinking up alternatives to fossil fuels, working out ways of making houses easier to heat, reducing the construction industry’s reliance on concrete, streamlining the world’s transport systems etc, etc. Some of these ideas and innovations will be brilliant – the majority, I hope.

But, drawing on my own experience as an engineer, I want to give an example of a brilliant idea that turned out not to be so brilliant, but still cost millions which were largely wasted. I trained as a civil engineer. This first degree saw me studying Chemistry, Physics and Maths, the building blocks for what I would go on to specialise in. The options for my Masters in civil engineering were Construction, Roads, Tunnels and other underground work, and Water & Environment. I chose the last, but to bridge the gap between my undergraduate status and becoming a post-grad, I had to research and write a thesis.

As my subject, I chose Biogas, a relatively new concept at that time whereby energy can be generated through anaerobic digestion, with biodegradable plants, food and farm waste being turned in energy in various forms. Plant and other biodegradable waste matter generate high levels of methane, a greenhouse gas much more dangerous as carbon dioxide, but that is controlled and contained in the production of biogas. There are other dangers in the disposal methods generally used to get rid of the world’s unwanted waste. Nitrates for instance can seep out of landfill sites and compromise drinking water, and untreated sewage and other farm waste pose an obvious risk to health. Vast landfill sites are both costly and will ultimately cause serious harm both to their local communities and to the planet. Biogas seemed to offer the almost magic solution to a growing problem, producing green energy and mitigating the threat of current disposal systems.

Governments began to provide subsidies for biogas plants and more and more farmers started to grow ‘energy crops’ – crops which had little or no food value, but which worked well in the bioreactors which were also being rolled out with government backing. It was perfect for politicians. It made it look as though they were doing something about climate change, and the idea of turning unwanted waste into green energy was easily grasped and obviously very attractive to voters as they became more attuned to the problems the world now faced.

But, as a scientist, I had one very simple question: Did the numbers add up? In other words, was the production of biogas actually producing the net benefits and the savings claimed? After intensive research, reviewing all the available facts, I concluded that it wasn’t. At least, not in the form that it had been pushed into by grants and subsidies which skewed the market. To take the most flagrant example of the process falling short, the land used to grow the energy crops was inevitably lost as a source of food, resulting in longer journeys for the food crops that had to be sourced further away from where they were consumed. This did not bother the big farmers, the businessmen, the millionaires. With the subsidies behind them, they were making big bucks and that was enough.

But when I came to draw up an Energy Balance Sheet at the end of my research, this model made no sense. By the time you accounted for the water, the fertilizer and the carbon cost of relocating the farming of land for food, the result, in terms of the professed goals, was barely positive. And this was proved as the subsidies gradually ran out and the market reasserted itself.

This is not to disparage biogas at all. Far from it. It just needs to be structured very differently. It needs to be decentralised, so that biogas plants are smaller but serve their immediate communities. Farm waste and indeed human waste is ideal for the process, as are the millions of tonnes of unwanted food that at least the richer countries in the world generate year in, year out. Decentralised, local biogas plants are a reminder of the importance of reducing our greenhouse gas emissions and also prove that saving the planet also helps at a local level. Because the benefits of intelligent disposal of waste matter are huge, both economically and in terms of health.

This has been recognised by NGOs and the great charitable trusts like the Gates Foundation. It’s not just diseases like measles and polio that need to be irradicated; death rates in the poorest countries remain high due to the lack of basic hygiene. Uncontaminated water for everyone on the planet should be a human right and anything that brings it closer should be supported. A research-based roll-out of biogas has the potential to bring that aim within reach, along with all the other benefits already discussed.

The point of revisiting my own university research is simply to illustrate that we must subject every new green proposal to scientific scrutiny before giving a hasty endorsement and establishing it with generous funding and subsidies. Facts, however surprising or even unwelcome, remain facts, and have to be acknowledged as the sole foundation for healthy progress. I’m going conclude this article by drawing further examples from a new book, A Trillion Trees, by the British environmentalist, Fred Pearce. Its subtitle is How We Can Reforest Our World, which is a cause close to my heart, and in which Eu Tech Chamber has had some involvement in the Great Green Wall project that is well on the way to establishing a continuous wall of trees right across Africa.

Pearce acknowledges that deforestation and the devastation it brings with it has been incessant throughout human history. Humans have reduced the forests of the world by half, and the destruction reached a pitch at the turn of the century, with whining chainsaws driving ever deeper into the Amazon, with uncontrollable fires doing even more damage. The recent Rang-tan film and campaign against Asian deforestation to make way for hundreds of thousand of palm trees to produce palm oil on an industrial scale is another example of human greed inflicting terrible harm on one of makind’s most vital resources.

Pearce gives his readers some comfort by pointing to the fact that reforestation is taking place, and that the target is the Trillion Trees of his title. And just to remind us why trees are so important, he describes the process whereby they pump water from the ground and release it as a vapour, sending ‘flying rivers’ to benefit the arid continental interiors. To put it in starkly simplistic terms, a single, mature tree might have the same cooling power as two domestic air-conditioning plants.

That is a heartening fact, reinforcing our commitment to protect trees where they stand and to plant more. But Pearce comes up with some other facts that may surprise and even shock. For instance, while commercial scale logging is without doubt the evil it is perceived to be, small-scale and illegal logging may, extraordinarily, not be such a bad thing. It can be much less damaging than the industrial scale version, and, so the research reveals, small scale logging can even spread biodiversity.

A final story from this stimulating book. Pearce travelled to a plantation in the Negev Desert in Israel. International donations have paid for hundreds of millions of Aleppo pines, with the best of ecological intentions. However, the fact is that, while each pine may amass between 500 and 800kg of carbon over a lifetime, the plantation is thought to be having an adverse effect, due to the ‘albedo effect’. Because it is so much darker than the desert sand it has replaced, it absorbs much more solar radiation, so the net outcome is negative. That will be disappointing news for the well-meaning donors whose generosity funded the plantation, but, to repeat, facts are facts, and however inconvenient, they must be recognised and respected so that our tireless commitment to reach a greener and more sustainable world goes forward with the highest chance of success. With so little time, we cannot afford to go down blind alleys, which will waste money and crucially eat up what little time we have.

Florian von Tucher