UK homes to be heated by human poo?                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

Aston University in Birmingham, UK, has been awarded a percentage of £4.5 million by Ofwat to embark on an intriguing new project, exploring the possibility of turning sewage sludge into usable resources such as clean water and energy.

Essentially, this somewhat controversial initiative will look at extracting energy from sewage and water treatment processes where the gases obtained from these processes - principally hydrogen and methane - could be used to power engines and heat homes.

This interesting and innovative project, named REvAR (Renewable Energy via Aqueous-phase Reforming) and carried out in collaboration with ICMEA-UK and Costain, transforms organic components in sewage sludge into liquid intermediates, which are then converted into fuel gases that can be used as heat and power.

If successful, this initiative would reuse and recycle millions of tonnes of sewage (i.e. human waste) that the water industry is struggling to manage; giving new purpose to natural waste and naturally derived gases - another potential feat for the renewable energy sector!

Within this, there are of course a few elements to consider:

Firstly, hydrogen is an expensive and therefore somewhat problematic gas when used within the context of heating homes due to the fact that hydrogen extraction, storage and transport is still both difficult and costly. What’s more, although burning hydrogen doesn’t produce carbon emissions and can be produced renewably (i.e. green hydrogen), it does produce nitrous oxides which are pollutants that can cause respiratory illnesses.

Secondly, using waste as feedstock to produce biogas to fuel our homes isn’t actually a brand new concept and something that farmers and commercial brands have used for many years via anaerobic digestion - beyond food & beverage waste and arable waste such as crop residue and herbal leys - two of the most widely used feedstocks in AD are in fact animal waste (i.e. manure) and sewage sludge.

What’s more, using human poo to heat and power homes in the UK and Europe is something experts have been discussing and experimenting with openly since at least 2010; the first UK homes were actually heated with human poo courtesy of Severn Trent Water in October 2014.

So why is this new project causing so much excitement and considered by the media as ‘innovative’?

Presumably because of the technique this new project is expected to use which combines hot-pressurised water with catalysts, aiming to achieve high conversion efficiency and reduce the energy intensity of the wastewater industry in the UK, coupled with the expected capacity of the project - potentially relieving the water industry of millions of tonnes of waste per year, consistently and sustainably, that could therefore heat a large proportion of homes throughout the country.

All of the above, plus the fact that the public may just be about ready to hear it and accept it.

We know that public opinion drives policy and if the general public feel comfortable and confident enough at any one time to accept a new energy source into their lives, said energy source will be made available for widespread adoption. And, particularly with the intensifying moves towards Net Zero within the next few years, the time could simply be right to introduce the concept of our entire country using our own waste as energy.

It will certainly be interesting to follow the progress of this project and see just where it goes!