The latest episode of Fully Charged raised as many questions as it answered which I am slowly learning is always the case.
Charge times are a very common anxiety. I'll explain as best I can. Using the lead supplied by Nissan which only carries 10 amps, the charge time from utterly empty to totally full is around 10 hours.
When I arrived at Tellisford Mill, due to the fact that I didn't have the correct lead to take the 440 volt (3 phase) charge (which would have taken around 20 minutes) I plugged in their 13 amp outlet and had to wait around for over 4 hours. To be honest this wasn't a chore, Anthony Battersby and Rachel Feilden who own Tellisford Mill were very hospitable. It was a public open day for them, they are part of the Mendip Power Group which is a group of people who live or own old wool and flour mills along the river Frome in Somerset.
If they had a web page explaining what they're doing I would have posted a link to it, there isn't so I'll do my best.
For a start, filming the actual turbine is impossible as it's buried beneath the mill. The only bit you can see (footage I shot on my phone) was taken in the very cramped room where it spins the actual generator.
The generators output is between 223,000 and 389,000 kwh per year with 330 litres a second passing through the turbine shaft which turns the turbine at a stately 136 rpm but with a torque of 520.6 Newton meters.
This whole set up cost some serious money, (I don't have figures) but they had to re-build the entire mill and dig out the old channel that once fed it, they also had to re-build the Saxon weir (the weir was built about 1,000 years ago) to push the water down the channel and through the mill. However now it's running, they supply all 30 houses in the village nearby and sell power to the grid. The whole project will pay for itself in 10 years and the turbine itself is built to run with minimum maintenance for 40 years. Annual maintenance costs are £120, that's for grease for the turbine and generator bearings. It has to be closed of for a couple of hours a year to enable this process.
Huge amounts of research have been done to discover if the fish population is affected by the turbine, they have discovered that fish stocks have increased since it's installation, but this is mainly do to improvements done to the weir, which has a fish run, and the trashrack that's fitted before the turbine entrance. This stops all but the smallest fish going through and the ones that do just get a bit dizzy and come out the other end unharmed.
The water flow in the river is not impeded, the way mills were developed over many centuries means they don't increase the risk of flooding, there are many 100's of old mill sites all over the country, including one near where I live, hence my desire to see what they had done.
So now, the Zero carbon claim. I think I made it clear enough. Producing the car, shed loads of carbon, producing the turbine, carbon city, it's a 7 ton steel monster made in Germany and shipped here. The actual energy that actually made the car move, the actual electrons stored in the battery, zero carbon. My argument is simple, you cannot achieve that in an internal combustion engine no matter what you do. The clue is in the name, combustion, burning. There was no burning taking place, the journey back from the mill to my house (68 miles) was my first Zero Carbon journey.
I am having a big slab of photo-voltaic panels fitted to the roof of my garage next month. Massive carbon footprint in production and installation, but once they are there... well, more on that soon.