Look at carbon, not energy

We urgently need a clear strategy for decarbonising the grid…and here’s why.

by thinkpanama, creative commons, flickr

The world is still awash with energy.

Peak oil may have passed but peak coal has not. Nor has peak gas, and nuclear and renewables are now a rising trend.  In other words, the problem is not a shortage of energy it is too much carbon.

The trouble is, at the moment it’s hard to find a quick and easy way of taking carbon out of the primary fuel mix. So, the focus is on reducing loads, getting more out of each unit of carbon fuel, and using so-called renewables to substitute for fossil fuel.

We’re too used to having energy on tap, generated and piped from a distance. Community scale services challenge this view of life (we’ll be debating this at our briefing). Low-carbon communities attempt to use waste in order to distribute relatively low-grade heat rather than high-grade energy.

This heat is ‘free’ insofar as it recovers energy from electrical generation, household waste, or from geothermal sources. Of course, nothing is actually free. Pipe work, pumping, capital costs and so forth means that fixed costs can exceed the notional cost of the primary fuel burned to generate distributed heat.

Because of high capital costs and the long lifetime of systems (like water mains), financial planning for low-carbon communities needs to take the long view.

We  don’t know what the carbon advantage of such systems will be in the future. If there is a significant and quick (economically speaking) rise in zero carbon wind and marine generation, and carbon sequestration in coal fired plants becomes the norm, then the carbon intensity of the grid will reduce to the point where the advantage of community based systems is lost.  In short the carbon arguments for community heating systems depend crucially on the speed of decarbonisation of the grid.

This is a community-scale heating dilemma. We should have invested in CHP/DH a couple of decades ago when we had access to North sea gas – instead we face the prospect of digging up the roads yet again and forcing householders to abandon their cherished boilers. But, without a guaranteed connected load and the effective displacement of high carbon intensity grid supply it will be difficult to make community scale heating financially attractive to a commercial investor.

So, we should focus on decarbonising the grid or develop heat-sharing technologies through low-carbon communities?  These are mega questions and need a national strategy where government must lead the way. What will be the role of the building services engineer and construction teams in planning and delivery whole-community solutions?