Anyway,
I'm skeptical but I really try to understand your project.
If I understand correctly, you try to be a kind of market carbon. Where people who lower their carbon emission get money (GreenCoin). But unlike the market carbon, pullutant people also get a reward (mining rigs dig GreenCoin even if they produce carbon because they use lot of electricity. Scrypt consuming more electricity than other popular algo.). Philosophically, I think it make no sense to pollute to reward environmentalists.
But this is not the biggest issue I have. If we talk strictly economics...
So we have miners who receive lot of coins that they will probably want to sell for bitcoins.
We have environmentalists that receive free coins, they will also probably want to sell for bitcoins.
That make a lot of people wanting to sell a lot of GreenCoins!
However, what are the incitatives to buy GreenCoins? If no one has reason to buy them, the price will fall. And soon, no one will want to buy the coin even at 1 Satoshi.
Maybe there is something that I don't understand?
With Scrypt ASICs coming out, I don't believe that mining Scrypt consumes more electricity than other coins - in fact, I think that argument is a bit of a moot point since it doesn't at all effect what we're trying to accomplish on a big enough scale.
Ultimately, you buy GreenCoin in order to offset your Carbon footprint. You make a long flight, and you buy the equivalent Carbon amount in GreenCoin. Don't imagine it as buying GreenCoin - think of it as buying and selling Carbon. That's the aim. BioDieselChris knows more about this, and I'll point him here.