Refrigerant Management and Building Envelope

Every refrigerator and air conditioner contains chemical refrigerants that absorb and release heat to enable chilling. Refrigerants, specifically CFCs and HCFCs, were once culprits in depleting the ozone layer. Thanks to the 1987 Montreal Protocol, they have been phased out. HFCs, the primary replacement, spare the ozone layer, but have 1,000 to 9,000 times greater capacity to warm the atmosphere than carbon dioxide.

In October 2016, officials from more than 170 countries met in Kigali, Rwanda, to negotiate a deal to address this problem. Through an amendment to the Montreal Protocol, the world will phase out HFCs—starting with high-income countries in 2019, then some low-income countries in 2024 and others in 2028. Substitutes are already on the market, including natural refrigerants such as propane and ammonium. [Source: https://www.drawdown.org/solutions/materials/refrigerant-management ]

A building envelope is comprised of the components that make up the shell of the building. The components separate the exterior from the interior of the building, and are designed to meet or exceed the needs of the specific application. The building envelope may also be described as what separates the interior areas that are temperature controlled (conditioned) space from exterior unheated (unconditioned) space. To break it down any area that is heated or air conditioned is considered a conditioned area where as any area that isn’t would be considered an unconditioned area. The building envelope must be designed with regard to climate, ventilation, and energy consumption within the building.

The many functions of the building envelope can be separated into three categories:

  • Support (to resist and transfer mechanical loads)
  • Control (the flow of matter and energy of all types)
  • Finish (to meet human desires on the inside and outside)

The control function is at the core of good performance, and in practice focuses, in order of importance, on rain, air, heat, and vapor control. [Source: https://www.reichelinsulation.com/Understanding-The-Building-Envelope.html ]

Floating Solar Farms

Millions of marine floating islands, each as large as a football field and powered by sunlight, could harvest carbon dioxide and produce enough fuel to power the world’s planes, ships, trains and lorries. These solar methanol farms, proposed by scientists from Switzerland and Norway, could even eliminate all global fossil fuel emissions.

Solar panels covering the 100m-diameter islands would provide energy for combining carbon dioxide and hydrogen into methanol – a compound that can either be used directly as a fuel or serve as a feedstock for petrochemical products. A chemical plant housed in a moored ship would provide the ingredients for this reaction: hydrogen from water splitting and carbon dioxide harvested from seawater. The area underneath the islands could even be used for fish farming.

A cluster of 70 islands could produce 1.75 tonnes of methanol per hour, the team calculates. To compensate for emissions from the long-haul transport, 170,000 such clusters would be needed. They could be placed along shorelines near the equator, in particular Indonesia, northern Australia and Brazil – areas that have lots of sunlight, small waves and few hurricanes. If 1.5% of the world’s oceans was used for solar methanol farms, they could offset global fossil fuel emissions altogether.

This vision, however, is not without its challenges. Electrolysing seawater creates unwanted chlorine, so the researchers suggest desalinating the water before use. Carbon dioxide can be harvested from seawater – its concentration here is 125 times higher than in air – but it requires heating or acidification. Electrodialysis, which effectively acidifies one part of a solution, could be a practical extraction method. Moreover, to be economically viable, each island cluster can’t cost more than $90 million (£70 million). At that rate it would be projected to cost $990,000,000,000,000 (nearly 1 quadrillion dollars).

The most challenging part, however, might be the catalytic methanol production. Current copper–zinc–aluminium catalysts require high pressures and temperatures. But if temperatures get too high, hydrogen and carbon dioxide can react to form unwanted carbon monoxide. Microstructured reactors and more selective nickel–gallium catalysts might alleviate these problems, but they still need to be tried and tested.

A lot of questions remain, such as whether these technologies could be combined in the way the scientists suggest, and what the best practical design for these facilities might be.

References

B D Patterson et al, Proc. Natl. Acad. Sci. USA, 2019, DOI: 10.1073/pnas.1902335116

Visit original article here: https://www.chemistryworld.com/news/11-million-floating-solar-farms-could-eliminate-carbon-emissions-from-transport-/3010580.article

Carbon Capture by RMIT University

The cost-effective method could revolutionize how we remove carbon from the atmosphere, particularly in regard to climate change.

A team of scientists used liquid metal and a liquid electrolyte to convert gaseous CO2 into a solid, coal-like substance.

Compared to current methods, the new approach could prove to be a more efficient and scalable way to remove carbon from the atmosphere and safely store it.

The United Nations Intergovernmental Panel on Climate Change says the global community must remove 100 billion to 1 trillion metric tons of carbon dioxide from the atmosphere by mid-century in order to avoid catastrophic global warming.

Scientists have created a method to convert carbon dioxide back into solid coal, a breakthrough that could change the ways carbon is removed from the atmosphere and permanently stored.

It’s one of several recently developed negative emissions techniques that seek to make carbon capture and storage cheaper, safer and more efficient. This particular method was developed by a research team led by RMIT University in Melbourne, Australia, and it uses a liquid metal electrocatalyst, containing nanoparticles of the rare-earth metal cerium, to convert the greenhouse gas into a stable, coal-like solid.

“While we can’t literally turn back time, turning carbon dioxide back into coal and burying it back in the ground is a bit like rewinding the emissions clock,” study co-author Dr. Torben Daeneke told The Independent. “To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially unviable.”

Original article on BigThink here!

ReTree

ReTree (verb): the act of replenishing the earth’s tree supply to help reverse climate change.

The mission of ReTree is to inspire people to help reverse climate change, one tree at a time. ReTree wants to plant 1 million trees in 2017.  And to accomplish this mission, ReTree will double the number of trees their donors plant for the entire year.

Our world is home to more than three trillion (3,000,000,000,000) trees! While that might seem like a large number, each day more than two and a half million (2,500,000) trees are destroyed. This constant and ongoing destruction has contributed (along with fossil fuel emissions) to a major issue for our planet: climate change.

When it happens naturally, as it did for millions of years, tree loss is a normal part of the cycle of life. A tree dies and another one grows. Now, with man’s interference and the loss of trees happening at an alarming rate, our planet can’t breathe. It was never designed to handle all that we’re putting it through. Climate change being at the top of the list.

Reducing factory and auto emissions might be the first thing you think of when tackling this global issue. Guess what? We don’t need fancy gadgets or millions invested in new technologies to fight climate change. There’s a simpler way to remove carbon dioxide from the air: trees!

Trees absorb CO2 from the air as they grow. Using energy from the sun, they turn the carbon captured from the CO2 molecules into building blocks for their trunks, branches, and foliage. This is all part of the carbon cycle and ReTree has created the simplest way to increase the number of trees and help reverse climate change.

Now multiply these results by thousands and millions of trees! We can’t stop climate change, but we can make an incredible impact, together, one tree at a time.

For more information visit ReTree online and start filling our forests!

Turning Coal Carbon Emissions to Baking Soda

A coal-powered plant in Tuticorin, India has found an innovative way to capture carbon emissions — by recycling them into soda ash, an ingredient in common household products like bleach, sweeteners, and even your toothpaste.

The typical carbon capturing method filters out the carbon before it is released into the atmosphere and stores it in a separate containment. But Tuticorin is changing it up by crystallizing the coal and turning it into soda ash — otherwise known as baking soda.

That baking soda byproduct means Tuticorin has made carbon capture profitable: Not only is it environmentally wise, but dirty waste is being re-imagined to sell plastic, rubber, or glass manufacturing.

With solar, wind, and hydropower resources becoming more accessible to the masses, the demand for natural gas is expected to be on the decline, making this carbon capture method attractive to businesses and consumers alike. According to the Ren21 Global Status Report for 2015, the world invested twice as much in clean energy as they did in the oil and gas industry. Previous roadblocks have stopped the U.S. from investing in carbon capture in the past. But this new mechanism can be outfitted to any plant — no matter how old — and is much more affordable.

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