About Incinerating Toilets
<<I’ll keep adding to this as time allows – pop back from time to time>>
We are seeing more talk and promotion of incinerating toilets which, whilst expensive, look nice and seem to offer a ‘perfect’ (if eco-unfriendly) solution. What they don’t tell you is how much energy/gas is used for evaporating urine – the focus is on the 300ml-500ml of poo/day per person. We’ve heard stories of 13Kg gas cylinders needing changing every two weeks since we produce a lot more urine than poo. The energy required to evaporate liquid is substantial (remember schooldays physics and the ‘latent heat of vaporisation’!) and a few people drinking and wee-ing will keep the toilet burner going for extended periods! the laws of physics show that it takes around five times as much energy to boil a liquid off than it takes to get it from 0C to 100C as water molecule bonds are very strong and these need to be broken to evaporate the water.
In principle, if you are on land and have access to unlimited mains power or gas and, probably, an additional toilet with a urine soak-pit, an incinerating toilet may be a good way to go. In our opinion, these toilets are ill-suited to an off-grid situation and careful consideration is needed along with real figures for solids+liquids incineration publicised.