Leader: At what price tidal power?

So it’s back to the drawing board on tidal power. The overarching review of the technology announced last week confirms what we already knew: the Treasury couldn’t come to an agreement with Swansea Bay developer Tidal Lagoon Power over the strike price for the flagship project. Small wonder, when TLP was originally seeking a strike price far above those of other energy projects – as much as £168 per megawatt-hour for 30 years was needed to get the project off the ground, according to one set of consultants. For a government that has already been battered for its proffered £92.50 strike price for Hinkley Point C, that’s simply a non-starter. Word is, the Treasury put a package on the table that was more in the region of the high £80s over 90 years. Even over such an unprecedented timescale, the sums just didn’t add up.

Over the next few months, Whitehall will be working frantically with industry and financiers to come up with a model that works. Not least among the questions to be answered is how on earth a 90-year strike price could be agreed, set and enforced? Surely a subsidy that lasts longer than the average life expectancy is nothing short of fantastical?

Yet these questions must be answered. Tidal power has huge potential for our island nation, as it could provide a baseline source of renewable generation that doesn’t have to wait for the wind to blow or the sun to shine. Get Swansea Bay developed at a high price, the theory goes, and more projects will follow at a much lower cost. Neither side can afford to walk away from this negotiation empty-handed.

• How refreshing it is to hear water company chief executives speak their minds. Comments this week from Anglian’s Peter Simpson and Northumbrian’s Heidi Mottram may not win them friends in all corners, but potential critics should remember that this is what healthy debate in a mature sector looks like (news, page 12). In the dark days of Section 13, the water companies attempted to agree and follow a party line, to their detriment. Since then, Ofwat has called for a grown-up conversation on the sector’s future, all the more important given the changes and challenges it faces. The comments this week, questioning the Treasury’s proposed timetable for domestic competition (Simpson), and competition’s implications for flood response (Mottram), show the companies’ willingness to engage in exactly that. Other parties will hold other views; we’d love to hear them too.