The energy will be provided, many reports have looked into this.
A modern high speed train uses less energy than a Pendelino, no one expect those opposed to the plan consider this to be an issue in 10 years when it opens.
How do you suggest we reduce the demand for travel?
The world over shows that as economies grow as does the demand for (rail) travel.
Take South Korea for example.
Fastest broadband on the planet.
Vast amounts of home working and video conferencing
Yet rail travel is going through the roof and they're massively expanding their high speed rail network
We either acknowledge that growing economies will lead to more travel or we somehow hope that the UK is unique and for some reason we can stop that growth in demand for rail travel despite all that we learn from our own history that is showing huge growth in demand for rail travel and internationally where this is mirrored.
The reason your Radio 2 travel report is as it is shows precisely why HS2 is being build, we've not invested in infrastructure in this country in the manner required so we've crap motorways, crap railways and crap airports.
Not addressing those issues simply ensures things never get better.
HS2 goes a long way to addressing the issues on the railway in London, Birmingham and Manchester.