The price of tidal power

When did it become OK to save our wildlife at the expense of everyone else’s?

There’s no joy in it but it’s got to be done. We have to press ahead with harvesting the tidal energy of the River Severn, despite the havoc it is likely to wreak on local wildlife, because these days there is no such thing as local wildlife.

When we talk about living in a globalised world, we don’t usually think about nations sharing wildlife. But we are now getting other people’s fish. Bluefin tuna and anchovies are increasingly common in British waters and no doubt we’ll be getting into fights with foreign fishing fleets about them soon. Elsewhere, species of Japanese coral are migrating northwards. A few weeks ago, Australian scientists issued a report into the ocean biodiversity in their region. Rather shockingly, their tropical fish are moving away – those that aren’t dying off in the rapidly warming water are migrating southwards, following the plankton that are being carried on currents that are rising in strength.

You won’t be surprised to hear that the blame for all this flux lies with global warming. Rising temperatures leave the inhabitants of the ocean no choice but to embrace change. Paradoxically, though, taking measures to combat global warming – such as building the Severn barrage to reduce our dependence on fossil fuels – will also force changes on the natural world. It’s now a question of whether we value our creatures more than everyone else’s.

The Severn provides Britain with a golden opportunity to exploit lunar power. The moon’s pull causes earth’s water to bulge out from the surface and the geometry of the Severn creates a bigger bulge than most. The difference between its high and low tide is the second largest in the world; only Canada’s Bay of Fundy can beat the Severn’s 14-metre pile of water.

Hold that heap of water back until just the right moment and the resulting torrent on release is a renewable source of energy. A Severn barrage would provide enough lunar electricity to power 5 per cent of Britain’s homes, equivalent to three nuclear or gas-fuelled power stations. It would also last three times longer – at least. According to projections, the barrage could operate for over a century, compared to the few decades of lifetime offered by a nuclear plant.

A cross-party group of MPs is backing a campaign for the barrage to be built and David Cameron has recently instructed the Energy Secretary, Ed Davey, to look at the proposal. It still might not take off, however. That is because, from a local perspective, it will be an environmental tragedy.

As with any hydroelectric project, holding back the water floods areas that would usually be dry. In the case of the Severn barrage, many of those areas are mudflats designated as sites of special scientific interest: feeding grounds for important bird species. It’s also worth mentioning that forcing the water through electricity-generating turbines at high pressure cannot help but hurt fish populations, too.

No pain, no gain

The consortium looking to build the barrage has come up with a design that, it claims, reduces mudflat loss by 60 per cent and operates at lower pressures, easing the toll on the Severn’s fish. Perhaps there are other mitigation efforts that can be made, such as constructing artificial mudflats at the water’s new edge. Either way, it is hard to see how we can justify holding back the barrage now. We will have to sacrifice some of our cherished natural environment.

As far as carbon-free, sustainable energy generation goes, this is the low-hanging fruit. If we don’t grab it, our continued emissions will have a similar, maybe greater, impact on biodiversity in other places. Yes, it will hurt but when did it become OK to save our wildlife at the expense of everyone else’s?

 

Surfers ride the Severn Bore along the River Severn. Photograph: Getty Images

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

Getty Images.
Show Hide image

The problems with ending encryption to fight terrorism

Forcing tech firms to create a "backdoor" to access messages would be a gift to cyber-hackers.

The UK has endured its worst terrorist atrocity since 7 July 2005 and the threat level has been raised to "critical" for the first time in a decade. Though election campaigning has been suspended, the debate over potential new powers has already begun.

Today's Sun reports that the Conservatives will seek to force technology companies to hand over encrypted messages to the police and security services. The new Technical Capability Notices were proposed by Amber Rudd following the Westminster terrorist attack and a month-long consultation closed last week. A Tory minister told the Sun: "We will do this as soon as we can after the election, as long as we get back in. The level of threat clearly proves there is no more time to waste now. The social media companies have been laughing in our faces for too long."

Put that way, the plan sounds reasonable (orders would be approved by the home secretary and a senior judge). But there are irrefutable problems. Encryption means tech firms such as WhatsApp and Apple can't simply "hand over" suspect messages - they can't access them at all. The technology is designed precisely so that conversations are genuinely private (unless a suspect's device is obtained or hacked into). Were companies to create an encryption "backdoor", as the government proposes, they would also create new opportunities for criminals and cyberhackers (as in the case of the recent NHS attack).

Ian Levy, the technical director of the National Cyber Security, told the New Statesman's Will Dunn earlier this year: "Nobody in this organisation or our parent organisation will ever ask for a 'back door' in a large-scale encryption system, because it's dumb."

But there is a more profound problem: once created, a technology cannot be uninvented. Should large tech firms end encryption, terrorists will merely turn to other, lesser-known platforms. The only means of barring UK citizens from using the service would be a Chinese-style "great firewall", cutting Britain off from the rest of the internet. In 2015, before entering the cabinet, Brexit Secretary David Davis warned of ending encryption: "Such a move would have had devastating consequences for all financial transactions and online commerce, not to mention the security of all personal data. Its consequences for the City do not bear thinking about."

Labour's manifesto pledged to "provide our security agencies with the resources and the powers they need to protect our country and keep us all safe." But added: "We will also ensure that such powers do not weaken our individual rights or civil liberties". The Liberal Democrats have vowed to "oppose Conservative attempts to undermine encryption."

But with a large Conservative majority inevitable, according to polls, ministers will be confident of winning parliamentary support for the plan. Only a rebellion led by Davis-esque liberals is likely to stop them.

George Eaton is political editor of the New Statesman.

0800 7318496