I am not the brightest with this stuff but I thought glass was supposed to be an environmentally friendly option. How can this be? Why are we switching the lights off to save energy, it all seems a bit pointless.
https://www.bbc.com/news/business-68429393
The furnace I saw in action at Stoelzle Flaconnage uses about 191,000 kWh of energy per day - that's enough to supply the average UK household with energy for 12 years.