If your jade goes below freezing, it may get damaged.

How much artificial light you get is up to you and your growing goals. If your new light is quite bright and your jade currently in low light, I would recommend slowly acclimating it.

Many options, depending on how many plants you have and how big they are. T5HO, CFL, and LED are probably all good options for you.

Thanks. I forgot to mention that I live in Utah, where we have inversion (aka very cloudy) for most of the winter, so the plant is going to go from about 10 hours of sunlight in the summer to maybe 4 in the winter. Right now I just have a jade plant (probably 8- 10" in diameter) and a small cactus that I will want to be under the light. I've read that the T5HO, in either 6500K or 3000K, depending on if you want to flower or maintain, are good options.

Get 6500k if you go T5HO, flowering vs. maintaining does not really apply to succulents unless you go really extreme on the ratio of red to blue light. This is based on scientific study (I can hunt for my source if you don't believe me). There is far too much misinformation on grow lights and plants.

I am 'flowering and maintaining' many succulents under my lights. Right now, here is what is budding/blooming for me: 2x Haworthia, 1x Echeveria, 1x Huernia, 1x Faucaria, 1x Aloe, 2x Lithops, 1x Lapidaria, 1x Neohenricia.

You might find this thread helpful, I've linked other threads in there with lots of good information as well.

http://forums.gardenweb.com/discussions/3414424/can-i-see-your-winter-setup?n=18

This is my Neohenricia sibbettii, which currently has over 7 flowers. =)

Awesome, thanks for the advice!

how far away are you keeping the light from the plants?

Jeremy - My lights are 2-3 inches away.

I don't think jade plants need that much light when they're semidormant over the winter.

I have a large specimen of "Gollum" that gets about half-day sun during its summer vacations outdoors. It has done fine indoors at 65 degrees either getting peripheral light from basement fluorescent light banks, or (currently) in my office at work, a couple feet below a four-tube overhead fixture.

Of course, it you want year-round expansive growth, both good light and warmth would be needed.

Jades actually should be winter growers? Mine have all really picked up over the last few months and are growing quite well now.

Agreed that if you want good growth, good light will be required with a bit of warmth. Mine are grown between 18-30C indoors right now.