I actually thought he had done some reading to come back with this one, silly me. The only reason he is pushing this is because they narrowly won the Uxbridge by-election on the ULEZ campaign. This is not going to work in a general election, but whatever it is the Tories throwing grenades to hide from their other failings.
Just as a point of interest the ULEZ was introduced by Johnson when he was Mayor of London, and the main reason Khan pushed it through was because he would have been refused a grant without a promise of implementing it from government. The was the Tories being arseholes because it is Labour ran.
Aside from this I actually agree with the ULEZ as it takes a lot of the crap off the road. It would only affect a very few people. How often do you see a white van doing more than the speed limit with a cloud of black crap coming out of the back of it. There are quite a few where I live.
The restrictions are: Diesels registered after 2015. These are shockingly bad for kids with asthma. Petrol models that are registered after 2005. There will not be many of these on the road. Buses and larger vehicles have tighter restrictions.
People who drive diesels around town thinking they are saving money are the worst. All cars after 2015 come with a DPF which filters the soot from the combustion. Making short journeys in a diesel will drastically reduce the life of the DPF. Google price says £1000-£3000 just for the part. You should be using a preventative treatment at the least annually, it will save you money in the long run. Diesel cars without a DPF filter are a health hazard to kids. The Netherlands is looking for a total ban on any diesel with a DPF from 2025 onwards. I would love to see that here.
As for the heat pumps, my opinion is that money could be spent more effectively elsewhere. They work, but the return can be marginal, and the cost is £7,000-£13,000. Solar panels give a much better return per pound than the cost of installing a heat pump in the UK. More so the further north you go. Scandinavian countries use heat pumps a lot. They manage because they build their housing much better standard than we do through experience with the cold weather. In the winter when the pumps are the least efficient you have to switch to an emersion style water heater. Scandinavian countries have a much lower cost for electricity than the UK. This means we would incur a higher cost to run these than they do which again makes it less sense economically.