Sounds like a topic for the Question Time board
No, biomass isn't an attempt to shore-up the current system. It can't be, because it requires a great deal of planning and research in the wider context of worldwide ecology.
There isn't one long term answer at the moment. Biomass could be eventually, or if we can get fusion working then there may be in the next 200 years or so - until then we have to use a diverse range of methods to, as you put it, shore-up the current system. But the current system isn't failing as far as I know, it's just not sustainable over the long term.