The letter on Wednesday (Clearer green energy targets are needed, 28 August) was quite right in recognising the UK’s lofty ambitions to become one of the cleanest and most innovative energy systems in the world on our path to becoming a net-zero emissions economy by 2050. But I take issue with the suggestion that our ambitions are not matched by our actions. We’re investing £274m to develop cheap, high-performance and durable batteries. We’re removing regulatory barriers to allow more storage facilities across the UK. We’re supporting small-scale localised energy generation through our smart export guarantee – continuing our world-leading support for the solar industry.

As members of the EU, we were obliged to implement the VAT increase for solar technology and storage. Once we leave, it may be possible to review this. All of this is supported by upgrades to the country’s energy infrastructure through our smart meter rollout and smart systems and flexibility plan. This enables homeowners to save money by putting them in control of their energy use, such as by charging electric vehicles or storing energy in a battery when it is cheapest.

As well as revolutionising how our energy is generated, transported and stored, the plan is ensuring our readiness for the growth of clean energy. Last year, low-carbon sources provided more than half our electricity and this is certain to grow as we allow renewables into the capacity market and end our reliance on coal by 2025. There is a £40bn prize for the taking; we have a plan and we’re acting on it.

Ian Duncan

Minister for climate change, Department for Business, Energy and Industrial Strategy

• Judge Richard Blake misses the point when he tells the Extinction Rebellion activists arrested for public order offences that “legitimate protests do not need to break the law” (Report, 23 August). Where has 30 years of “legitimate” protesting got us?

Extinction Rebellion disruption pales into insignificance when seen in the context of the climate and social disruption that is coming down the road. History has shown peaceful civil disobedience and personal sacrifice to be (perhaps the only) effective tools to bring about system change. Which is why I and thousands of other are preparing for rebellion in October. If we do nothing we stand to lose everything anyway, so what’s to fear?

Carol Blumenthal

Andover, Hampshire

• I worked in Texas for a year in 1969. Expecting the weather to be hot, I was amazed to find I was frozen in air conditioning in buildings and homes (Blowing cold and hot , 29 August). I used to walk outside every hour to heat up until I earned enough money to buy a warm cardigan. I was delighted when the air conditioning broke down for a week and temperatures returned to what I regarded as comfortable. In the present English record-breaking temperatures I manage to keep my house comfortable by judicious use of indoor and outdoor blinds and opening and closing windows according to the outside temperature. It would be even better if installers of European shutters were more available here. Air conditioning adding to more global warming is not a good solution.

Wendy Mulville

Maldon, Essex

• I look forward to reading Steve Edwards’s post-apocalyptic novel when it appears (Letters, 29 August). But he should be aware that in 500 years there will be no human communities – small, scientific, scholarly or otherwise – to consider what happened in the 21st century. The ecosystem required to support a complex species such as ours will have been eliminated by the biodiversity crash, insectageddon, the climate crisis, and the mass release of global warming gases from dying forests, Arctic permafrosts and the deep oceans. In 500 years from now, the crumbling remains of our cities and towns will be ruled by cockroaches and rats, who of course have no capacity to investigate the catastrophe that rendered us extinct.

Joseph Nicholas

Tottenham, London

• Regarding the furore about Brazil’s Amazon forest fires, I would like to point out that all built-up areas across the world were once mostly forested, and were cleared for homes and farming. Britain, the US, Canada, New Zealand, Russia, Australia, South Africa and others have all cut down millions of acres of forested areas over several hundred years. We call the Amazon the “lungs of the world”. But let’s not forget that most of the other lungs of the world we have already destroyed. When Europeans arrived in North America it was impossible to travel without entering forests. Let’s not forget our past contribution to climate change.

Michael Cook

Poole, Dorset

• Seven years ago, Britain hosted an Olympic Games that had set out to “inspire a generation”. And it delivered. The baton was duly passed to Brazil in 2016, who called for um novo mundo, a new world. Yet now Brazil’s government backs the destruction of rainforests. Our leaders seem unwilling to respond to the science. The Arctic melts, oceans acidify and wildfires rage, all as never before. That “new world” – our world – faces an existential threat, the climate and ecological crises. Thankfully, the 16-year-old climate activist Greta Thunberg asks: “Where are the adults?”

We sporting champions hear your call, Greta. Your courage and clarity have inspired us, and called us into the arena. Sport brings communities together across the globe and teaches us how to dream big, make sacrifices, push beyond perceived limits, and rise to the occasion. We now mobilise these qualities in support of Earth – alongside all young people fighting not just for their own future, but that of all life. While acknowledging that we and our sports must continue to reduce our environmental impact, we are stepping up in the spirit of fair play, teamwork and empowerment. And we call on other athletes and “everyday champions” to step up too, for in these times every person has the power to lead. Let us all unite as “Champions for Earth”, standing with young people all across the world for the global climate strike on 20 September.

Anna Bentley-Ward Olympian 2012, fencing

Tim Brabants, Olympian (gold and two bronze) 2000, 2004, 2008, 2012, canoeing

Heather Fisher Olympian 2016. rugby 7s

Rebecca Gallantree Olympian 2008, 2012 and 2016. Diving

Helen Glover Olympian (2 Gold) 2012, 2016, rowing

Laurence Halsted, Olympian 2012 and 2016, fencing. The True Athlete Project

Dr Clare Halsted, Olympian 1972 and 1976, fencing

Dave Hampton, World Championships, 1982, rowing. Founder, Champions For Earth

Joie Leigh GB & England International, hockey

Willi Moore, Olympian 1972 (bronze), cycling

Erin Nayler, Olympian 2016, New Zealand, football

Pauline Peel née Bird Olympian 1976 and 1980, rowing

Katie Rood New Zealand International, football

Goldie Sayers, Olympian (bronze), 2004, 2008, 2012, athletics

Greg Searle Olympian (gold and two bronze) 1992, 1996, 2000 and 2012, rowing

Etienne Stott, Olympian 2012 (gold), canoeing

Dan Tipney Junior international 2001-04, rowing. Co-founder, Rowers Against Rubbish

Anna Turney, Paralympian 2010 and 2014, Alpine skiing. The True Athlete Project

Melissa Wilson World Championships, 2017 and 2018, rowing

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