As UK Trade and Industry Secretary Alistair Darling prepared to launch yesterday's energy white paper, National Grid and its Dutch counterpart, TenneT, were launching their £410m joint venture to install a 1000-megawatt subsea electricity interconnector between the Netherlands and Kent.

Due to be operational by 2010, BritNed will supplement the existing 2000mw link between England and France. Capacity on both lines will be auctioned to electricity supply companies to import or export power as demand fluctuates. The objective is to further enhance "security of supply" at both ends of the supply chain.

Security of supply loomed large in Darling's statement to the Commons. His white paper aims to tackle two problems, he said: the need to cut greenhouse gas emissions, and the need, in an increasingly volatile world, to secure future energy supplies.

"Both are vital for our future. Both are global issues, calling for action internationally as well as here at home," the minister warned.

He plans, subject to a new round of consultation, to sanction a new generation of nuclear stations to help plug any supply gap as older fossil-fired and nuclear power stations close by the early 2020s.

Of course, Scotland already has an established interconnector link with the English grid network. It has operated for many years typically, because of Scotland's historic excess generating capacity, by sending power south.

Scotland can still generate around 20% more power than it needs. But the big, unanswered question is whether that apparently comfortable margin could be reversed over the next couple of decades as our two nuclear stations and other established generating plant reach the end of their operational lives.

Depending on what choices are made to replace that lost capacity, could Scotland find itself a net importer of power? In particular, if Hunterston and Torness close as currently planned, in 2011 and 2023 respectively, could we conceivably replace all that baseload of electricity by non-nuclear means alone?

It's a huge issue, not least for Scotland's ability to continue to promote itself as a place to do business. Companies need to know they can keep their lights on (and their computers and processes running, too) if they are to feel comfortable staying or locating here.

The new minority SNP government at Holyrood, just as committed to higher growth as its predecessor, does not appear to see security of supply in our own domestic electricity market as an issue now or in any foreseeable future.

Yesterday, in Aberdeen, the new Scottish Energy Minister, Jim Mather, described all predictions of a future energy gap occurring here as older plant closes as "ridiculous".

Later, as he set out his governing vision to MSPs, First Minister Alex Salmond was even more dismissive of any talk of the lights going out here.

There is already, he pointed out, almost as much installed renewable capacity (hydro, wind, biomass, etc) here as nuclear capacity (2452mw versus 2465mw). Soon, renewables capacity will comfortably outstrip nuclear, he added. Why then is nuclear's contribution to power generated in Scotland running at 38% of the total, while renewables supply just 13%?

Well you can't drain a dam the way you can run Torness week-in, week-out, on baseload. Nor can you always depend on a turbine to turn if there's no wind. Of course, nuclear power stations do suffer outages, sometimes unexpectedly. That said, comparing installed nuclear and renewable capacities is like comparing apples and oranges.

And that's the nub. When the new Scottish government says the lights in Scotland will never go out, it risks betting its own long-standing and consistent hostility to any new nuclear capacity ever being built in Scotland against rapid and reliable operational returns from a variety of highly promising, but as yet unproven, alternative technologies.

A few months ago the SNP wanted the European Commission to step in and prevent the Spanish utility Iberdrola snapping up ScottishPower. Last week, Salmond used his first official engagement to meet Iberdrola's chairman, Ignacio Galan, at Longannet, and praise the group's plans to introduce cleaner coal technology both there and at Cockenzie.

Now anything that reduces the output of carbon into the atmosphere from Longannet or any other coal-fired power station is hugely welcome. Given that at best it would reduce these emissions by a fifth, any demonstrable project to capture the remaining carbon and re-inject it into the earth's crust would be even better.

But coal-fired stations like Longannet will remain major polluters, even with supercritical turbines and boilers installed. In addition, the stations will have to operate on reduced capacity as any conversion takes place, further compromising supply. And, like greener technologies harnessing wave and tidal power, full carbon capture has yet to be demonstrated, anywhere in the world, as operationally viable.

The SNP will insist on its no new nuclear stance, whatever anyone says. But that does, of course, still leave some wriggle room.

In the new spirit of consensus, can we assume that any application from British Energy to extend the operational lives of Hunterston and/or Torness (something that falls outwith their legislative competence under the 1989 Electricity Act) our new devolved government will bite its tongue? Let's hope so.