Land use planning needs to undergo a systemic revolution in its tools and methods to achieve net zero.
This needs to include but go well beyond plot by plot design.
Take for example a tree. As it grows it absorbs CO2. When it dies it rots and releases it, the carbon cyle.
If that tree is used as a building material it becomes ‘stock’ of carbon and release is delayed, so long as it is used, reused or recycled. If the wood or disused building materials is burned it releases it – it becomes a flow and increases atmospheric CO2. If you replant in forests trees more quickly they become a new carbon sink, at least temporarily. Though there is no enough land on the planet for this to be an effective geo-engineering strategy.
Take energy recovery. A few years ago this was seen as unproblematic renewal energy. Now it is a net carbon release problem. The two energy recovery plants approved in the last years in the UK each have conditions requiring best in class carbon capture technology to be used over their lifetimes, even if that technology hasn’t been invented yet. Yes I’m skeptical of that, I think we have to shift to anaerobic methods of energy recovery (even if the technology is still flaky) which produces biochar as ‘waste product’ which can be fed back to soils and is carbon negative. Yet this is an example of planning hesitantly and pragmatically creating solutions for net zero and understanding that solutions will evolve rapidly.
Recently I got into a twitter discussion about the possibility of zero carbon construction where I suggested using softwood. I was criticised because the person said cutting down trees released carbon and you could never replant trees fast enough. I suspect they had read an article on the carbon effects of deforestation effects for charcoal and confused it with commercial forestry. What this does illustrate though is the need to understand the lifecycle carbon costs of building materials and the opportunity costs of building (i.e. what alternatives the site could be put to). These issues are complex and require a systems level understanding of land use and land use economics, rate of change of inputs and rate of change of outputs – wasn’t it always thus.
A systems level understanding is essential because across a spatial plane it is quite possible to have intensification of agriculture on one part, urbanisation with improved biodiversity on another, more forestry on another part, and rewilding on what remains – and not starve and not die.
There is a cohort of those who, failing to take a systems view, looking at each site individually, believe there is no solution and so we must stop building all together. What this paleolithic brand of Nimbyism take out of the equation is people. If humanity died off the planet would be better off so no need to build houses or improve human welfare as development and ‘growth’ is bad. This kind of misanthropic Nimbysim cannot be bought off with better design and more participative planning, though other brands can be. This brand – the Advocado Nimbys (Pretending to be green but espousing brown policies identical to fascism once you scratch the surface) must be defeated not placated, because if they are not defeated people die because of a defeatist attitude to global warming and extinction to which the poorest and unhoused suffer first. Worst of all they have no plan to go carbon negative, and throw global warming into reverse, because they see it as a technological fix and some kind of evil conspiratorial plot by profit seekers.
Planning thinking has nowhere near enough understanding of the global systems of land use to be able to see, definitively, what zero carbon planning is. However we have to learn, and the best way to learn is to do. Its like broccoli – its time to stop pushing it around on the plate and start eating some.