If he gets a generator the options are diesel which are the most reliable and natural gas. A 6000 watt natural gas generator will do 3 1000 watt lights on the 12 12 flower no problem and is whisper quiet. If two people were sitting on it while it was running they would not need to raise there voices in order to talk. Another benefit is CO2 is the biproduct. Diesel or biodesiel is the most reliable and if you got a pick up truck you will be able to get a tank to fit your bed for stealth fill ups. With 5000 watts running constant you are looking at spending around 1000 a month or more in fuel to operate. Just a small amount of what you will be making. The natural gas unless you live near a airport of which most have fill stations you will need a couple different companies to deliever to you or get an excuse for useing it. You could say you use it to heat and power your house heat a garage or some thing. Just put out some non working halogen lights that look like they come on at night. They are 1500 watts a piece. I would not go much over 500 with a non private electric company. Most gas companies are private and will not complain about making them money. Still its one more person to smell the garden. I recommend you line the room in pond liner. Get a generator that can handle twice the watts you run through it. Diesels are reallt the only ones designed to run all day.

Hope this helps
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