Hi Jules,
No problem at all! 24V would be fine; you will need to reduce stage current very slightly for the input pair to compensate the increase in voltage; I forget the resistor number, will look it up for you, it's a 10K standup in the centre of the pcb which links to the two 10R emitter degen resistors of the LTP. Move it up to 12K, no other changes.... The idea is to pull back offset to less than 5mV.
BUT, would not current draws from other appliances cause fairly massive spikes at turn-on? We are talking 10-20A peaks here....
How many batteries do you have in your domestic power supply? French deep cycle 2V? Say 24 of them in series/parallel? Takes me back to my 32V days on a country property. I remember the fiscal pain of replacing those batteries every 5-10 years, it cost a fortune. This is the one aspect of home power that really discourages me - and it's the same for hybrid cars. I'm told the Prius power pack is 144 x 1.5V small batteries, giving 216V fully charged. Cost is around $US4K for a new pack, life around 8-10 years. It would be interesting to examine the Lexus 430 hybrid - a MUCH bigger system with reputedly 330Kw on tap.
The conversion is slow.

I've looked at three 1991 engines, rejected them all at this stage, and am reading up avidly on the net to find all the pitfalls. I have composed a very comprehensive 63 page document of net takes on the swap, it's extremely involved, and then it might be difficult and costly to get it through registration. There is only 3/4" inch clearance left and right of the engine, and clearance of the steering shaft is problematic around the right bank exhaust header. The V8 is around 80 Kgs lighter, and mounts are no problem at all. The car as it stands is entirely rust free, beautiful condition throughout, but worth about $1K, so I have to do something reasonably quickly. I haven't run out of Cressys yet, however, as my wife has an identical model with even lower mileage.
Still, the bike runs like a dream, so it ain't all bad......
Cheers,
Hugh