Right now it's not as good as it could be because half the miners are situated in China, which uses a lot of coal to produce energy. Now, there are alternatives that can be implemented to help reduce Bitcoins carbon footprint.
-Hydro electricity
-Wind farms
-Solar energy
-Burning waste to generate electricity
These aren't necessarily new ideas but they are possible ways to help offload some of the energy that's used with cleaner alternatives. But, that's probably not as viable at the moment. Maybe with partnerships, or government incentives we can help drive faster clean energy adoption.
The other solution is of course: A new cryptocurrency
There are less energy intensive platforms that could take over as the de facto coin that would provide far less energy requirements than bitcoin.
People who think cryptocurrencies are extremely important for society tend to have less of a problem with the energy usage, says Marcovici, at Hydrominer, in Austria. People who are not so much fans of them are the ones who are driving the discussion about energy. Its a philosophical question.