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The controversial future of nuclear power in the U.S.

Lois Parshley

President Joe Biden has set ambitious goals for fighting climate change: To cut U.S. carbon emissions in half by 2030 and to have a net-zero carbon economy by 2050. The plan requires electricity generation – the easiest economic sector to green, analysts say – to be carbon-free by 2035.

A few figures from the U.S. Energy Information Administration (EIA) illustrate the challenge. In 2020 the United States generated about four trillion kilowatt-hours of electricity. Some 60 percent of that came from burning fossil fuels, mostly natural gas, in some 10,000 generators, large and small, around the country. All of that electricity will need to be replaced - and more, because demand for electricity is expected to rise, especially if we power more cars with it.

Renewable energy sources like solar and wind have grown faster than expected; together with hydroelectric, they surpassed coal for the first time ever in 2019 and now produce 20 percent of U.S. electricity. In February the EIA projected that renewables were on track to produce more than 40 percent by 2050 - remarkable growth, perhaps, but still well short of what’s needed to decarbonize the grid by 2035 and forestall the climate crisis.

This daunting challenge has recently led some environmentalists to reconsider an alternative they had long been wary of: nuclear power.

Nuclear power has a lot going for it. Its carbon footprint is equivalent to wind, less than solar, and orders of magnitude less than coal. Nuclear power plants take up far less space on the landscape than solar or wind farms, and they produce power even at night or on calm days. In 2020 they generated as much electricity in the U.S. as renewables did, a fifth of the total.

But debates rage over whether nuclear should be a big part of the climate solution in the U.S. The majority of American nuclear plants today are approaching the end of their design life, and only one has been built in the last 20 years. Nuclear proponents are now banking on next-generation designs, like small, modular versions of conventional light-water reactors, or advanced reactors designed to be safer, cheaper, and more flexible.

“We’ve innovated so little in the past half-century, there’s a lot of ground to gain,” says Ashley Finan, the director of the National Reactor Innovation Center at the Idaho National Laboratory. Yet an expansion of nuclear power faces some serious hurdles, and the perennial concerns about safety and long-lived radioactive waste may not be the biggest: Critics also say nuclear reactors are simply too expensive and take too long to build to be of much help with the climate crisis.

While environmental opposition may have been the primary force hindering nuclear development in the 1980s and 90s, now the biggest challenge may be costs. Few nuclear plants have been built in the U.S. recently because they are very expensive to build here, which makes the price of their energy high.

Jacopo Buongiorno, a professor of nuclear science and engineering at MIT, led a group of scientists who recently completed a two-year study examining the future of nuclear energy in the U.S. and western Europe. They found that “without cost reductions, nuclear energy will not play a significant role” in decarbonizing the power sector.

“In the West, the nuclear industry has substantially lost its ability to build large plants,” Buongiorno says, pointing to Southern Company’s effort to add two new reactors to Plant Vogtle in Waynesboro, Georgia. They have been under construction since 2013, are now billions of dollars over budget - the cost has more than doubled - and years behind schedule. In France, ranked second after the U.S. in nuclear generation, a new reactor in Flamanville is a decade late and more than three times over budget.

“We have clearly lost the know-how to build traditional gigawatt-scale nuclear power plants,” Buongiorno says. Because no new plants were built in the U.S. for decades, he and his colleagues found, the teams working on a project like Vogtle haven’t had the learning experiences needed to do the job efficiently. That leads to construction delays that drive up costs.

Elsewhere, reactors are still being built at lower cost, “largely in places where they build projects on budget, and on schedule,” Finan explains. China and South Korea are the leaders. (To be fair, several of China’s recent large-scale reactors have also had cost overruns and delays.)

“The cost of nuclear power in Asia has been a quarter, or less, of new builds in the West,” Finan says. Much lower labor costs are one reason, according to both Finan and the MIT report, but better project management is another.

Available at: https://www.nationalgeographic.com/environment/ article/nuclear-plants-are-closing-in-the-us-should-we-build-more. Retrieved on: Feb. 3, 2022. Adapted.

In the fragment of paragraph 2 “because demand for electricity is expected to rise, especially if we power more cars with it”, is expected to rise is used to

 

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The controversial future of nuclear power in the U.S.

Lois Parshley

President Joe Biden has set ambitious goals for fighting climate change: To cut U.S. carbon emissions in half by 2030 and to have a net-zero carbon economy by 2050. The plan requires electricity generation – the easiest economic sector to green, analysts say – to be carbon-free by 2035.

A few figures from the U.S. Energy Information Administration (EIA) illustrate the challenge. In 2020 the United States generated about four trillion kilowatt-hours of electricity. Some 60 percent of that came from burning fossil fuels, mostly natural gas, in some 10,000 generators, large and small, around the country. All of that electricity will need to be replaced - and more, because demand for electricity is expected to rise, especially if we power more cars with it.

Renewable energy sources like solar and wind have grown faster than expected; together with hydroelectric, they surpassed coal for the first time ever in 2019 and now produce 20 percent of U.S. electricity. In February the EIA projected that renewables were on track to produce more than 40 percent by 2050 - remarkable growth, perhaps, but still well short of what’s needed to decarbonize the grid by 2035 and forestall the climate crisis.

This daunting challenge has recently led some environmentalists to reconsider an alternative they had long been wary of: nuclear power.

Nuclear power has a lot going for it. Its carbon footprint is equivalent to wind, less than solar, and orders of magnitude less than coal. Nuclear power plants take up far less space on the landscape than solar or wind farms, and they produce power even at night or on calm days. In 2020 they generated as much electricity in the U.S. as renewables did, a fifth of the total.

But debates rage over whether nuclear should be a big part of the climate solution in the U.S. The majority of American nuclear plants today are approaching the end of their design life, and only one has been built in the last 20 years. Nuclear proponents are now banking on next-generation designs, like small, modular versions of conventional light-water reactors, or advanced reactors designed to be safer, cheaper, and more flexible.

“We’ve innovated so little in the past half-century, there’s a lot of ground to gain,” says Ashley Finan, the director of the National Reactor Innovation Center at the Idaho National Laboratory. Yet an expansion of nuclear power faces some serious hurdles, and the perennial concerns about safety and long-lived radioactive waste may not be the biggest: Critics also say nuclear reactors are simply too expensive and take too long to build to be of much help with the climate crisis.

While environmental opposition may have been the primary force hindering nuclear development in the 1980s and 90s, now the biggest challenge may be costs. Few nuclear plants have been built in the U.S. recently because they are very expensive to build here, which makes the price of their energy high.

Jacopo Buongiorno, a professor of nuclear science and engineering at MIT, led a group of scientists who recently completed a two-year study examining the future of nuclear energy in the U.S. and western Europe. They found that “without cost reductions, nuclear energy will not play a significant role” in decarbonizing the power sector.

“In the West, the nuclear industry has substantially lost its ability to build large plants,” Buongiorno says, pointing to Southern Company’s effort to add two new reactors to Plant Vogtle in Waynesboro, Georgia. They have been under construction since 2013, are now billions of dollars over budget - the cost has more than doubled - and years behind schedule. In France, ranked second after the U.S. in nuclear generation, a new reactor in Flamanville is a decade late and more than three times over budget.

“We have clearly lost the know-how to build traditional gigawatt-scale nuclear power plants,” Buongiorno says. Because no new plants were built in the U.S. for decades, he and his colleagues found, the teams working on a project like Vogtle haven’t had the learning experiences needed to do the job efficiently. That leads to construction delays that drive up costs.

Elsewhere, reactors are still being built at lower cost, “largely in places where they build projects on budget, and on schedule,” Finan explains. China and South Korea are the leaders. (To be fair, several of China’s recent large-scale reactors have also had cost overruns and delays.)

“The cost of nuclear power in Asia has been a quarter, or less, of new builds in the West,” Finan says. Much lower labor costs are one reason, according to both Finan and the MIT report, but better project management is another.

Available at: https://www.nationalgeographic.com/environment/ article/nuclear-plants-are-closing-in-the-us-should-we-build-more. Retrieved on: Feb. 3, 2022. Adapted.

In the fragment of paragraph 1 “The plan requires electricity generation – the easiest economic sector to green, analysts say – to be carbon-free by 2035”, to green means to

 

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De acordo com as exigências da norma-padrão da Língua Portuguesa, a palavra destacada está corretamente empregada em:

 

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De acordo com as exigências da norma-padrão da Língua Portuguesa, o verbo destacado está corretamente empregado em:

 

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A palavra destacada está adequada ao contexto da frase, de acordo com o seu significado dicionarizado, em:

 

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O emprego da vírgula está plenamente de acordo com as exigências da norma-padrão da Língua Portuguesa em:

 

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O acento grave indicativo de crase está empregado de acordo com a norma-padrão da Língua Portuguesa na palavra destacada em:

 

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A concordância verbal está de acordo com a norma-padrão da Língua Portuguesa em:

 

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Entulho eletrônico: risco iminente para a saúde e o ambiente

Os resíduos de equipamentos eletroeletrônicos (lixo eletroeletrônico) são, por definição, produtos que têm componentes elétricos e eletrônicos e que, por razões de obsolescência (perspectiva ou programada) e impossibilidade de conserto, são descartados pelos consumidores. Os exemplos mais comuns são televisores e equipamentos de informática e telefonia, mas a lista inclui eletrodomésticos, equipamentos médicos, brinquedos, sistemas de alarme, automação e controle.

Obsolescência programada é a decisão intencional de fabricar um produto que se torne obsoleto ou não funcional após certo tempo, para forçar o consumidor a comprar uma nova geração desse produto. Já a obsolescência perspectiva é uma forma de reduzir a vida útil de produtos ainda funcionais. Nesse caso, são lançadas novas gerações com aparência inovadora e pequenas mudanças funcionais, dando à geração em uso aspecto de ultrapassada, o que induz o consumidor à troca.

O lixo eletroeletrônico é mais um desafio que se soma aos problemas ambientais da atualidade. O consumidor raramente reflete sobre as consequências do consumo crescente desses produtos, preocupando- se em satisfazer suas necessidades. Afinal, eletroeletrônicos são tidos como sinônimos de melhor qualidade de vida, e a explosão da indústria da informação é uma força motriz da sociedade, oferecendo ferramentas para rápidos avanços na economia e no desenvolvimento social. O mundo globalizado impõe uma constante busca de informações em tempo real, e a sua interação com novas tecnologias traz maiores oportunidades e benefícios, segundo estudo da Organização das Nações Unidas (ONU). Tudo isso exerce um fascínio irresistível para os jovens.

Dois aspectos justificam a inclusão dos eletroeletrônicos entre as preocupações da ONU: as vendas crescentes, em especial nos mercados emergentes (inclusive o Brasil), e a presença de metais e substâncias tóxicas em muitos componentes, trazendo risco à saúde e ao meio ambiente. Segundo a ONU, são gerados hoje 150 milhões de toneladas de lixo eletroeletrônico por ano, e esse tipo de resíduo cresce a uma velocidade três a cinco vezes maior que a do lixo urbano.

AFONSO, J. C. Revista Ciência Hoje, n. 314, maio 2014. São Paulo: SBPC. Disponível em: https://cienciahoje.periodicos.capes. gov.br/storage/acervo/ch/ch_314.pdf. Adaptado.

No 3º parágrafo, no trecho “a explosão da indústria da informação é uma força motriz da sociedade”, a palavra destacada pode ser substituída, sem prejuízo de sentido, por

 

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Entulho eletrônico: risco iminente para a saúde e o ambiente

Os resíduos de equipamentos eletroeletrônicos (lixo eletroeletrônico) são, por definição, produtos que têm componentes elétricos e eletrônicos e que, por razões de obsolescência (perspectiva ou programada) e impossibilidade de conserto, são descartados pelos consumidores. Os exemplos mais comuns são televisores e equipamentos de informática e telefonia, mas a lista inclui eletrodomésticos, equipamentos médicos, brinquedos, sistemas de alarme, automação e controle.

Obsolescência programada é a decisão intencional de fabricar um produto que se torne obsoleto ou não funcional após certo tempo, para forçar o consumidor a comprar uma nova geração desse produto. Já a obsolescência perspectiva é uma forma de reduzir a vida útil de produtos ainda funcionais. Nesse caso, são lançadas novas gerações com aparência inovadora e pequenas mudanças funcionais, dando à geração em uso aspecto de ultrapassada, o que induz o consumidor à troca.

O lixo eletroeletrônico é mais um desafio que se soma aos problemas ambientais da atualidade. O consumidor raramente reflete sobre as consequências do consumo crescente desses produtos, preocupando- se em satisfazer suas necessidades. Afinal, eletroeletrônicos são tidos como sinônimos de melhor qualidade de vida, e a explosão da indústria da informação é uma força motriz da sociedade, oferecendo ferramentas para rápidos avanços na economia e no desenvolvimento social. O mundo globalizado impõe uma constante busca de informações em tempo real, e a sua interação com novas tecnologias traz maiores oportunidades e benefícios, segundo estudo da Organização das Nações Unidas (ONU). Tudo isso exerce um fascínio irresistível para os jovens.

Dois aspectos justificam a inclusão dos eletroeletrônicos entre as preocupações da ONU: as vendas crescentes, em especial nos mercados emergentes (inclusive o Brasil), e a presença de metais e substâncias tóxicas em muitos componentes, trazendo risco à saúde e ao meio ambiente. Segundo a ONU, são gerados hoje 150 milhões de toneladas de lixo eletroeletrônico por ano, e esse tipo de resíduo cresce a uma velocidade três a cinco vezes maior que a do lixo urbano.

AFONSO, J. C. Revista Ciência Hoje, n. 314, maio 2014. São Paulo: SBPC. Disponível em: https://cienciahoje.periodicos.capes. gov.br/storage/acervo/ch/ch_314.pdf. Adaptado.

No trecho do 3º parágrafo “segundo estudo da Organização das Nações Unidas”, a palavra destacada expressa ideia de

 

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