jumsumtak is spot on about Fuqua, as always, and I'll add my 2 cents about Yale.
The great thing about Yale in this regard is that you don't have to be a joint degree to see how much love students have for the Energy field here. There are a lot of opportunities for you to work with energy/sustainability organizations while you're still a student. There are student clubs that you can take advantage of both at SOM as well as the Forestry school, and you'll no doubt have a ton of engagement with the joint degrees as well.
Someone in my learning team came in like you, with just an interest in energy, and actually ended up applying to Forestry joint degree while he was here ... so if you want to pursue the joint degree later, you could look into that too.
Happy to connect you with folks at SOM interested in energy or any joint degrees. PM me if you want to do that or to chat further.
//Fuqua does have better weather though, sigh.
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