Tag Archives: Carbon dioxide

Environmentally friendly concrete – the Roman or French model?

As was widely reported in July, a research team led by Paulo Monteiro (professor of civil and environmental engineering) of the US Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley, had been analyzing samples from a 2,000-year-old Roman concrete breakwater to determine why Roman seawater concrete is so durable, how its manufacture was more environmentally sound, and how to adapt those characteristics to modern concrete production.

“It’s not that modern concrete isn’t good. It’s so good we use 19 billion tons of it a year,” Monteiro said in a 2013 news release. “The problem is that manufacturing Portland cement accounts for seven percent of the carbon dioxide that industry puts into the air.”

Analysis of samples provided by team member Marie Jackson pinpointed why the best Roman concrete found in 2,000-year-old Roman piers, massive breakwaters, Trajans Markets (below) and the Pantheon in Rome, was superior to most modern concrete in durability.

Phys.org™ a leading web-based science, research and technology news service, updated this news in a July article. Ms Jackson and her colleagues found that seawater filtering through the concrete leads to the growth of interlocking minerals that lend the concrete added cohesion: when seawater percolated through the concrete in breakwaters and in piers, it dissolved components of the volcanic ash and allowed new minerals to grow from the highly alkaline leached fluids.

Marie Jackson says that the mineral intergrowths between the aggregate and the mortar prevent cracks from lengthening, while the surfaces of nonreactive aggregates in Portland cement only help cracks propagate farther. The results are published in American Mineralogist.

As ‘tufo’ volcanic rocks (tuff), common in and around Rome, are not found in many parts of the world, the team is experimenting with substitutions. A more immediate innovation, we suggest, would be further use of the ancient and durable French hemcrete or hempcrete (isochanvre) in Europe. For more information go to: https://en.wikipedia.org/wiki/Hempcrete.

 

 

 

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Is mitigation an acceptable strategy in the transition to lower emissions?

A 2015 International Energy Agency report sees coal demand outside China ‘modestly increasing’ through 2020 as the decline in Europe and the United States will be ‘more than offset’ by growth in India and Southeast Asia.

quartzIf this is so, should we welcome the news in Quartz magazine that Carbon Clean Solutions technology could help to reach the low carbon-emissions targets set out in the Paris climate agreement?

Carbon Clean Solutions is a ‘20-person company’ with headquarters in London, employees in India and the US. It was founded in 2009 by two chemical engineers, Aniruddha Sharma and Prateek Bumb.

The company built a plant in Tuticorin in southern India which captures carbon dioxide from its coal-fired boiler and converts it into soda ash – and did it so cheaply that it did not need any government subsidies.

“So far the ideas for carbon capture have mostly looked at big projects, and the risk is so high they are very expensive to finance. We want to set up small-scale plants that de-risk the technology by making it a completely normal commercial option.” Sharma told the Guardian.

ccs-headerThis informative website was set up in 2013 but has not been updated

Carbon Clean Solutions technology is said to be cost effective to install and also to run: at a recent industry conference, Professor Peter Styring (University of Sheffield) is widely quoted as saying that the true cost of carbon emissions, measured through environmental degradation, is close to $30 per ton. Sharma says the plant captures emissions from coal at a cost of about $30 per ton and adds, “The next generation of the technology we are working on could cut the price down to $15 per ton”.

The author of the Quartz article, Akhat Rashi, points out that the earlier emphasis on carbon capture and storage (CCS), has shifted in part to carbon capture and utilisation (CCU), where the emissions are turned into useful products.

Mr Rashi adds that the proportion of global renewable energy supply is increasing rapidly, but not yet fast enough to keep global temperatures from rising 2°C above the pre-industrial average, which is estimated to be the point at which that climate change reaches a critical point of no return – so we ask readers, is Carbon Clean Solutions technology a useful and acceptable strategy in the transition to lower emissions?

Jeremy Heighway comments:

Maybe it depends on what mitigation means in newspeak. Lessening negative effects to what extent? How much reliance is there going to be on something positive arriving that tops the negatives?

As far as the text goes, carbon capture and utilisation is better than carbon capture and storage in my book (except that a living tree would out-perform the book I’d be reading from in terms of CCU)!  

I guess a more serious response is that of course mitigation CAN be an acceptable PART OF THE strategy, yes, but it doesn’t make it the solution per se.

 

 

 

Will a new ‘electric system’ eventually replace the ‘old dumb grid’?

Some time ago, a reader from Tokyo sent a link to a Forbes article by Chicago-based Jeff McMahon, who covers news of green technology, energy and the environment.

He reports that, in a North Western University debate on the future of nuclear power sponsored by students agitating for a “Fossil Free NU,” Jordi Roglans-Ribas, the director of the Nuclear Engineering Division of Argonne National Laboratory, argued that any future free of fossil fuels would need nuclear power, which provides carbon-free energy 24 hours a day, supplying the reliability lacking in renewables like solar and wind.

arne gundersenArnie Gundersen – popular with readers of a sister site – called the claim a marketing ploy: “We all know that the wind doesn’t blow consistently and the sun doesn’t shine every day, but the nuclear industry would have you believe that humankind is smart enough to develop techniques to store nuclear waste for a quarter of a million years, but at the same time human kind is so dumb we can’t figure out a way to store solar electricity overnight. To me that doesn’t make sense.”

Then Gundersen told the audience about Elon Musk, the founder of PayPal , chairman of SpaceX and SolarCity and product architect for Tesla Motors.

tesla elon musk

A few hours later Musk announced the launch of Tesla Energy, ”a suite of batteries for homes, businesses, and utilities fostering a clean energy ecosystem and helping wean the world off fossil fuels.” Tesla will sell the home battery, the Tesla Powerwall, for $3,500, a fraction of the $13,000 price observers had expected, and perhaps more importantly, a fraction of the cost of the $10,000 battery announced earlier this week by European competitors Sungevity and Sonnenbatterie.

In a May Wall Street Journal article, he is said to predict that demand will range from countries where solar is popular, such as Germany, to developing economies that don’t have existing power lines.

A British answer to the Tesla home battery

powervaultOn June 23rd, in an article by Andrew Bounds, Enterprise Editor of the Financial Times, we read that Powervault, a crowdfunded London start-up, says its power storage unit which slides under the kitchen worktop to capture and use surplus electricity generated by domestic solar panels is cheaper, more practical and targeted at the British consumer, than Tesla’s wall-mounted home battery:

Not to be confused with the Dell Powervault, “This is a complete system in a box, is compatible with all solar systems and takes about an hour to install,” says Joe Warren, managing director. He expects Powervault units — which can store 2 or 4 kilowatt hours — will cost £2,000-£2,800, but believes the price will drop to £1,000 within three years because of advances in battery technology. Tesla’s system costs about $5,000 once extras and installation is added. The larger home model can store enough electricity to power a home for 10 hours.

As electricity prices rise and grids come under strain, many other companies are exploring the use of home or locally generated power from renewable sources.

McMahon comments that much of the “old dumb grid—in which electricity flowed in one direction from centralized power plants to largely passive consumers—is not nimble enough to accommodate change”.

In a June article for Forbes, he reports that Bryan Hannegan, who leads the National Renewable Energy Laboratory team working to increase reliability and performance, reduce cost, and minimize environmental impacts of energy systems, says that a new electric system, transformed by distributed generation and storage, “used to be 10 years away, now it’s five, maybe even less, In some places it’s actually even here today.”

Gundersen summarises:

“The operative word in this discussion tonight is now. What are we going to do now to reduce the amount of carbon dioxide going into the atmosphere?” He lists ‘things’ which can be implemented immediately:

  • We know how to insulate a building.
  • We know how to put double and triple-pane windows in them.
  • We know how to build windmills and put solar cells up.
  • We don’t have to invest $50 trillion and wait 15 years for that to come to fruition.

“Producing our way out of the problem with renewables is half the solution. Conserving our way out is the other half.”


Stop press:

Again a lead from Tokyo:

Yet-Ming Chiang a Taiwanese-American materials-science professor at the Massachusetts Institute of Technology, says that when his company starts commercial sales in about two years, it will slash the cost of an entry-level battery plant 10-fold, as well as cut around 30% off the price of the batteries themselves. A new manufacturing process using a powerful new cell adds energy while stripping away cost will allow lithium-ion batteries to begin to compete with fossil fuels.

 

Efforts to tackle climate change more effective than expected?

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iea logoEarlier this month the Financial Times reported the International Energy Agency findings that global emissions of carbon dioxide, the most long-lasting greenhouse gas, did not rise in 2014 – for the first time in 40 years. Though the global economy grew 3%, the amount of CO2 pumped out remained at the 2013 level of 32.3bn tonnes. Two factors were mentioned:

  • China has cut its use of coal, one of the biggest sources of carbon emissions, and installed more hydroelectricity, wind and solar power, imposed energy efficiency standards for industry, shut older factories and shifted away from the heavy manufacturing that has powered its economic growth.
  • Wealthy OECD countries have started to “decouple” economic expansion from emissions increases as they install more renewable energy plants and set a range of stricter standards on car fuel economy and home appliance energy use.

The IEA is to publish a June 15 report advising governments what energy measures should be agreed at a December meeting of the United Nations Framework Convention on Climate Change in Paris where world leaders are due to finalise a global climate change pact.

Affordable solar home systems in Bangladesh

 

Yunus solar4

 

Shafi Chowdhury sent news from the Daily Star ‘s report that Nobel Laureate Professor Muhammad Yunus and the Grameen Shakti team have installed more than one million solar home systems across Bangladesh.

The systems are now 100% Bangladeshi and operated by the local people. Grameen Shakti is providing microcredits to help people buy solar home systems with a three-year monthly payment system costing is the same as a family spends on kerosene. By 2012, the company had also installed 595,516 improved cooking stoves and 24,206 biogas plants.

Ellen Goldstein, country director of the World Bank, which has given subsidies  for the project, said this is an impressive achievement: “When the programme was initiated, the target was only 500,000 solar home systems in five years. Now the partners are installing 60,000 systems per month”.

roof top solar bangladesh

Solar systems are helping reduce footprint by replacing polluting kerosene-fired lanterns and helping reduce deforestation. The scheme also creates local jobs and income opportunities. Some women have doubled their income and become energy distributors as a result of the electricity.

Bilkis Begum, who installed a solar home system at her home in Gazipur with the help of Grameen Shakti, described how the life of her family members has changed. “My sons are now able to study at night. I also prepare products from bamboo and canes at night with five women from the area.”

Every solar home system unit helps to cut 0.232 tonnes of carbon dioxide every year. Altogether, the solar home systems installed so far brought a CDM (clean development mechanism) benefit for Bangladesh at $2.32 million a year.