Expensive. I think they get used a lot by people growing certain crops in the attic.
They're not THAT expensive unless you're talking about LED lights. That said, it does depend on how big your greenhouse is. If you need a lot of lights, your power consumption will increase dramatically, but the heat from the lights will heat up your greenhouse, so you'll save some money there.
What is it you need to grow through winter? If you're hoping for a self sufficient garden and never visiting the supermarket again you'd be better off growing seasonal appropriate fruit and vegetables.
loony gardner says:Lol Fidget really? I guess the 'attic farmers' can afford the expense See original post
I confess I thought the same as Fidget when I saw this post. Attic gardeners however have dubious methods for going around the electricity meter to help keep profits high. Not quite growing your own fresh salad is it!