Tech Tent: Will better batteries persuade us to go electric?

This week, the UK government announced that sales of new petrol and diesel cars will be banned from 2030 - just one signal among many around the world that a major shift to low-carbon motoring is under way.

In practice, that means millions of people are going to have to be persuaded to choose an electric car - and on this week's Tech Tent we explore how improvements in battery technology can make that happen.

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The last decade has seen major advances in battery-powered motoring, with Elon Musk's Tesla leading the way in showing that electric cars don't have to be ugly - and they don't have to stop every 20 miles to recharge.

But anxiety over the cars' range, charging availability and initial cost are still issues for potential buyers.

Colin Herron, an automotive engineer who worked for Nissan for many years and is now a consultant on low-carbon vehicle technology, tells Tech Tent there are reasons to be cheerful about future advances in batteries. Lithium-ion batteries are the first target.

"We will be tampering with this battery over the next four or five years, and putting more additives in will get about another 20% boost in performance," he explains.

But he says the big leap forward will come with solid state batteries, which will appear first in mobile phones and laptops before they progress to cars. They promise to be a safer and lighter option, and researchers believe they can offer much faster charging.

"They're all targeting 10 to 12 minutes. That's what they think is the 'stop time', the convenient time to check your email for people who are moving on."

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Herron believes, however, that we will all need to change the way we think about motoring in the electric era: using trains for longer journeys, and keeping the car for shorter local trips where stopping to charge will not be necessary.

And he cautions that we also need to realise that describing electric motoring as "zero carbon" may be wide of the mark: "It's emission-free motoring, but the car has to be built, the battery has to be built, and the electricity does come from somewhere."

On that theme, we also hear how one African country is making progress towards a zero-carbon future. Wangari Muchiri, a renewable energy engineer based in Kenya, tells us the country's electricity grid is almost entirely dependent on renewable energy.

"The biggest private sector investment in Kenyan history has actually been in wind energy," she says. "And we're now seeing that, slowly, as people become more confident, investors become more confident with the Kenyan landscape."

The problem is that around half the population, particularly in rural areas, is not connected to the grid, and more than 80% of Kenyans depend on burning wood and other biomass materials for cooking and heating.

Muchiri is involved in a number of projects to build a series of mini-grids, using wind and solar energy to bring less-polluting electricity to rural Kenya.

Also on this week's programme

When much of the world went into lockdown back in the spring, technology proved a vital tool for young people, whether to continue their education or to communicate with friends and family. The Cambridge University psychologist Dr Amy Orben, who researches the impact of technology on mental health, tells us the pandemic has changed how we think about this issue.

She says politicians and the public had often assumed that time spent using technology was time not doing something better. "Lockdown really challenged that idea, and it needed to be challenged," she says.

"For example, for certain disadvantaged groups, it might be a really important way of getting information and getting in contact with people like you, if - for instance - you're an LGBTQ teen in a very small town."

This week also saw a study from the Oxford Internet Institute, which found that video games aren't necessarily bad for your mental health, and can contribute to your sense of wellbeing.

From the spread of misinformation to online bullying, we've heard plenty about the negative aspects of technology this year - but the pandemic has also shown us what a positive force it can be.