L’opérateur Xcel Energy a alerté fin novembre les autorités sanitaires que 1,5 million de litres d’eau contenant du tritium s’étaient échappés d’une conduite de sa centrale nucléaire de Monticello. Le Minnesota, qui en a informé le public jeudi 16 mars, estime qu’il n’y a pas de risque sanitaire.

L’autorité de sécurité nucléaire américaine “surveille la décontamination d’une fuite [de 1,5 million] de litres d’eau radioactive provenant de la centrale nucléaire de Monticello”, dans l’État du Minnesota, rapporte CBS News. L’opérateur de la centrale, Xcel Energy, affirme que l’incident ne présente aucun danger pour le public.

La fuite d’eau contient du tritium. Cet isotope radioactif de l’hydrogène est un effluent courant et sous surveillance des centrales nucléaires. Signalée fin novembre aux autorités du Minnesota, la fuite n’a été rendue publique que jeudi 16 mars.

Chris Clark, le directeur de la centrale, explique à la chaîne américaine :

“Si à un moment donné, il y avait eu la moindre inquiétude pour la sécurité du public, nous aurions bien sûr immédiatement fourni plus d’informations.”

Xcel Energy a repéré la fuite le 21 novembre dans “une conduite entre deux bâtiments de sa centrale”, située “à quelque 56 kilomètres de la ville la plus peuplée de l’État, Minneapolis, en amont du fleuve Mississippi”, précise la BBC. Selon les autorités sanitaires du Minnesota, la fuite “n’a pas atteint le fleuve Mississippi” ni contaminé le réseau d’eau potable.

“Environ un quart du tritium déversé a été récupéré jusqu’à présent”, ajoute le site de la chaîne publique britannique.

World Opinions – Courrier international

L’article États-Unis. Fuite d’eau contaminée dans une centrale nucléaire du Minnesota est apparu en premier sur زوايا ميادين | Mayadin Columns.

A major breakthrough has been announced by US scientists in the race to recreate nuclear fusion.

Physicists have pursued the technology for decades as it promises a potential source of near-limitless clean energy.

On Tuesday researchers confirmed they have overcome a major barrier – producing more energy from a fusion experiment than was put in.

But experts say there is still some way to go before fusion powers homes.

The experiment took place at the National Ignition Facility at the Lawrence Livermore National Laboratory (LLNL) in California.

LLNL director Dr Kim Budil said: “This is a historic achievement… over the past 60 years thousands of people have contributed to this endeavour and it took real vision to get us here.”

Nuclear fusion is described as the “holy grail” of energy production. It is the process that powers the Sun and other stars.

It works by taking pairs of light atoms and forcing them together – this “fusion” releases a lot of energy.

It is the opposite of nuclear fission, where heavy atoms are split apart. Fission is the technology currently used in nuclear power stations, but the process also produces a lot of waste that continues to give out radiation for a long time. It can be dangerous and must be stored safely.

Nuclear fusion produces far more energy, and only small amounts of short-lived radioactive waste. And importantly, the process produces no greenhouse gas emissions and therefore does not contribute to climate change.

But one of the challenges is that forcing and keeping the elements together in fusion requires very high temperatures and pressures. Until now, no experiment has managed to produce more energy than the amount put in to make it work.

How close is a fusion-powered future?

The amount of energy they’ve generated in this experiment is tiny – just enough to boil a few kettles. But what it represents is huge.

The promise of a fusion-powered future is one step closer. But there’s still a long way to go before this becomes a reality.

This experiment shows that the science works. Before scientists can even think about scaling it up, it needs to be repeated, perfected, and the amount of energy it generates will have to be significantly boosted.

This experiment has cost billions of dollars – fusion does not come cheap. But the promise of a source of clean energy will certainly be a big incentive for overcoming these challenges.

The National Ignition Facility in California is a $3.5bn (£2.85bn) experiment.

It puts a tiny amount of hydrogen into a capsule the size of a peppercorn.

Then a powerful 192-beam laser is used to heat and compress the hydrogen fuel.

The laser is so strong it can heat the capsule to 100 million degrees Celsius – hotter than the centre of the Sun, and compress it to more than 100 billion times that of Earth’s atmosphere.

Under these forces the capsule begins to implode on itself, forcing the hydrogen atoms to fuse and release energy.

On announcing the breakthrough Dr. Marvin Adams deputy administrator for defense programs at the US National Nuclear Security Administration said that the laboratory’s lasers had input 2.05 megajoules (MJ) of energy to the target, which had then produced 3.15 MJ of fusion energy output.

Dr Melanie Windridge, CEO of Fusion Energy Insights, told the BBC: “Fusion has been exciting scientists since they first figured out what was causing the Sun to shine. These results today really put us on the path to the commercialization of the technology.”

Prof Jeremy P. Chittenden, professor of plasma physics and co-director of the Centre for Inertial Fusion Studies at Imperial College London called it “a true breakthrough moment”.

“It proves that the long sought-after goal, the ‘holy grail’ of fusion, can indeed be achieved,” he said.

This has been the sentiment echoed by physicists globally, who praised the work of the international science community.

Prof Gianluca Gregori, Professor of Physics at the University of Oxford said: “Today’s success rests upon the work done by many scientists in the US, UK and around the world. With ignition now achieved, not only fusion energy is unlocked, but also a door is opening to new science.”

On the question of how long before we could see fusion being used in power stations, Dr Budil, the LLNL director, said there were still significant hurdles but that: “with concerted efforts and investment, a few decades of research on the underlying technologies could put us in a position to build a power plant”.

This is progress from when scientists used to say 50 – 60 years in answer to that question.

One of the main hurdles is getting cost down and scaling up the energy output.

The experiment was only able to produce enough energy to boil about 15-20 kettles and required billions of dollars of investment. And although the experiment got more energy out than the laser put in, this did not include the energy needed to make the lasers work – which was far greater that the amount of energy the hydrogen produced.

World Opinions – BBC News

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Europe is sweltering during a prolonged summer heatwave. But the attention of political leaders is increasingly focused on the coming winter. As a succession of recent warnings from the International Energy Agency (IEA) and elsewhere has underlined, an energy crisis to rival the oil price shock in the 1970s could hit when the weather turns cold.

As Vladimir Putin seeks to make the west pay for its support for Ukraine since February’s brutal invasion, Moscow has intensified its squeeze on gas exports to Europe. On Monday, Russia shut down its main pipeline to Germany – having previously reduced the flow of gas through it by 60%. Ostensibly, Nord Stream 1 has been closed to allow scheduled maintenance work, but its reopening later this month is far from certain. Gas supplies to Italy have been reduced by a further third; in all, a total of 12 EU countries have been either fully or partially cut off from Russian gas supplies. Supplies are accordingly dwindling before the period when they will be most needed. And, amid shortages and outages, European gas prices are almost 10 times higher than in the US.

Matters could get worse. The IEA has cautioned that rationing of fuel to industry, and even households, may become necessary if Mr Putin moves to a complete cutoff of gas supplies over the winter. As Russian troops expand their occupation of eastern Ukraine, the Kremlin is aiming to exert economic leverage over Europe’s response through a form of energy blackmail. Last week, Mr Putin threatened to unleash “catastrophic consequences” on markets if the west instituted further sanctions, such as a mooted cap on oil prices.

A freezing winter, soaring inflation and the wider cost of living crisis could tip millions of families over the edge, undermining support for sanctions on Russia and western solidarity with Ukraine. Without significant intervention to protect vulnerable people and ease hardship, there is a risk that, as the European Commission vice-president, Frans Timmermans, told the Guardian last week, countries will descend into “very, very strong conflict and strife”.

A concerted response is therefore urgently required. Having belatedly recognised the dangers of oil and gas dependency on Moscow, governments above all need to accelerate the pace of transition to renewables and promote energy efficiency. But that will be a process which takes years, not months. Alternatives to Russian energy are, meanwhile, proving difficult to access in sufficient quantity. The immediate problem of getting through the winter will require decisive action in the short term, including energy conservation to build up gas stockpiles for the winter. The gravity of the moment is illustrated by the decision of Germany’s green minister for climate action, Robert Habeck, to reactivate mothballed coal-fired power plants. At an emergency meeting later this month, EU leaders will collectively discuss winter contingency plans. A pan-European energy “solidarity plan” will need to ensure a fair distribution of gas supplies in the event of severe shortages, and establish common rules for identifying priorities.

Before the invasion, European governments were hoping to return to a form of political and economic normality after Covid. Instead they find themselves confronted with another existential threat requiring emergency measures. To face down Mr Putin’s threats this winter, and maintain a united front in support of Ukraine, a pandemic-style sense of collective solidarity will need to be fostered. It will not come cheap.

World Opinions – The Guardian View

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Prices in the US rose faster than expected last month, as rising energy and food costs pushed inflation to the highest rate since 1981.

The annual inflation rate rose to 8.6% in May, the Labor Department said, after easing in April.

The rising cost of living has been squeezing households and putting pressure on policymakers to bring the issue under control.

The US central bank has been raising interest rates since March.

Analysts had hoped that the moves were starting to work to cool economic activity, easing the price pressures. But the conflict between Russia and Ukraine, which has driven up the price of oil and commodities like wheat as it disrupts exports from the two countries, has made tackling the problem more difficult.

Food prices were up more than 10% last month compared to May 2021, while energy surged more than 34%.

But Friday’s report showed the increases continue to spread throughout the economy, pushing the cost of everything from airline tickets and clothing to medical services higher.

“So much for the idea that inflation has peaked. Consumer prices blew past expectations – and not in a good way with the 8.6% annual increase the fastest in more than 40 years,” said Greg McBride, chief financial analyst at Bankrate.com.

“Worse the increases were nearly ubiquitous. Just no place to hide.”

The US has been grappling with rising prices since last year, when an unexpectedly strong economic rebound from the shock of the pandemic – driven by large doses of US government spending, including direct cheques to households – overwhelmed supplies, prompting companies to raise prices.

Now the war in Ukraine has spread the problem around the world, with Covid related shutdowns in China this spring contributing.

As the rising costs hit household purchasing power and prompt a pullback in spending, officials are warning that growth in many countries is at risk of a sharp downturn.

“The war in Ukraine, lockdowns in China, supply-chain disruptions, and the risk of stagflation are hammering growth. For many countries, recession will be hard to avoid,” World Bank President David Malpass said this week.

US stock markets fell in the wake of the inflation reports, with all three major indexes dropping more than 2%. The falls added to weeks of declines in US shares, as investors become nervous about the path for the economy.

“Even if inflation peaks soon, it’s unlikely to decelerate quickly.” said Richard Flynn. managing director of Charles Schwab UK. “High prices may put pressure on consumer spending into the medium term.

“Add ongoing supply-chain problems and the economic impact of Russia’s invasion of Ukraine to the threat of inflation, and it’s easy to see why fears of a downturn have risen swiftly.”

Polls show a majority of Americans see inflation as the top problem facing the country. Consumer sentiment has plunged and US President Joe Biden’s approval ratings have sunk as Republicans criticise him over the issue.

In hearings in Washington this week, US Treasury Secretary Janet Yellen said bringing down prices was the “number one priority”.

Over the month, prices gained 1%, driven by rising cost of petrol, which has hit new records in the US, approaching an average of nearly $5 a gallon.

Wages have not kept up with the rising prices. The rising cost of living has especially hit lower income households, for whom basics like food and energy make up large portions of spending.

By Natalie Sherman Business reporter, New York – BBC News

L’article Energy and food drive US inflation to highest for 40 years est apparu en premier sur زوايا ميادين | Mayadin Columns.

An astonishing global shift is under way: 127 countries have now stated that by mid-century their overall emissions of carbon dioxide will be zero. That includes the EU, US, and UK by 2050 – and China by 2060. Companies are enthusiastically signing up to similar “net zero” goals. Finally the international community seems to have accepted the scientific fact that we need to stop adding greenhouse gases to the atmosphere to stabilise our climate. Dare we hope that the climate crisis can be brought under control?

Perhaps, but big problems remain. Long-term commitments have not resulted in sufficient near-term actions. The world is on track for emissions to be just 0.5% below 2010 levels by 2030, compared with the 45% needed on the road to net zero by 2050. The pivotal Glasgow Cop26 climate talks in November will need to tackle this. But a more insidious problem is emerging. Net zero increasingly involves highly questionable carbon accounting. As a result, the new politics swirling around net zero targets is rapidly becoming a confusing and dangerous mix of pragmatism, self-delusion and weapons-grade greenwash.

The science of net zero is simple: every sector of every country in the world needs to be, on average, zero emissions. We know how to do this for electricity, cars, buildings and even a lot of heavy industry. But in certain areas, including air travel and some agricultural emissions, there is no prospect of getting to zero emissions in the near future. For these residual emissions, greenhouse gasses will need to be sucked out of the atmosphere at the same rate as they are added, so that, on average, there are net zero emissions.

Making this work requires carbon removal, also known as “negative emissions”. This can be low-tech, like restoring forests, as this takes carbon out of the atmosphere and stores it in trees. Or it can be hi-tech, like using chemicals to strip carbon dioxide from the atmosphere and then pumping it deep underground into safe geological storage. In theory this is all fine, as pragmatically some carbon removal is needed to balance hard-to-reduce emissions: but negative emissions and offsetting alone are not a route to net zero.

In practice, by believing in the promise of these methods, we are too often deceiving ourselves, in three major ways. The first is an unrealistic overreliance on carbon removal to preserve the status quo. Shell recently published its net zero plan, that actually projects high oil and gas production through to 2050 and beyond, which voila, are magically removed with negative emissions. Critically, there is far too little land to plant enough trees to counter today’s emissions, and large-scale hi-tech methods do not yet exist.

The second deception is in offsetting against notional emissions trajectories instead of removing carbon from the atmosphere. Mark Carney, the ex-governor of the Bank of England and climate adviser to Boris Johnson, recently described his $600bn Brookfield Asset Management portfolio as “carbon neutral”, despite investing in fossil fuels. Carney said: “The reason we’re net zero is that we have this enormous renewables business.” He went on to claim that renewables avoid carbon emissions that would otherwise have happened, so they “offset” his investments in fossil fuel emissions. This is not net zero. It is an accounting trick. Emitting carbon at the same time as building solar capability does not equal zero emissions overall. Offsetting needs to be used to remove carbon dioxide from the atmosphere to counter difficult-to-remove emissions, and not just be an enabler of business-as-nearly-usual.

The third deception comes from not getting what you think you’re paying for in the self-regulated global carbon market. The commercial carbon offset concept relies on “additionality” – that money paid then reduces emissions or captures carbon that would not otherwise have happened. A recent report I advised on showed that the offsets market is awash with old legacy carbon credits where that assumption is violated,some 600m tonnes of these environmentally poor-quality credits are available to buy, six times the current size of the voluntary carbon market. These old credits come from projects that have already happened, meaning buying additional credits provides no additional climate benefit. Energy giant Total recently bought these near-worthless credits.

What is to be done? Negative emissions and offsets are here to stay. In a limited way, they are needed to stabilise the climate as they are the only way to tackle the hardest-to-eliminate emissions. Urgent discussion is needed about what comprises a “residual emission” that requires offsetting. In practical terms, making the carbon accountancy trustworthy will require truly independent regulation that is based on science. It is the only way to contain the bad actors and release the capital of good actors. Solving these carbon deceptions should be a core outcome of the Glasgow Cop26 climate summit.

If such deceptions remain, disaster looms. Big finance, led by Carney, is planning to massively expand carbon markets. Conceivably, new carbon-based financial products could boom, with little impact on emissions. Just like the sub-prime crisis, few will understand what they bought, and another globe-spanning crash could sweep the world, compounding economic and climate crises causing mass suffering, as we realise again that the Earth owes us nothing. Nature doesn’t do bailouts.

 By Simon Lewis is professor of global change science at University College London and University of Leeds, and the author, with Mark Maslin, of The Human Planet: How We Created the Anthropocene – theguardian.com

L’article The climate crisis can’t be solved by carbon accounting tricks est apparu en premier sur زوايا ميادين | Mayadin Columns.