From NOT A LOT OF PEOPLE KNOW THAT

By Paul Homewood

Can renewable energy ever replace fossil fuels?

Fossil Fuels v Renewable Energy?

Let me start by stating that I am not pro or anti anything. In a free market, the best technologies, solutions and products automatically come to the fore, without the need for subsidies, regulations and mandates.

If renewable energy is all that is promised, it will do the same.

There is of course no doubt that the cheap, abundant and reliable energy provided by fossil fuels has transformed society and made all of us better off than ever before in so many ways.

We get rid of them at our peril!

So far, our transition to renewable energy in the UK has been painfully slow and extremely expensive. Wind and solar power still supply only 3% of the UK’s total energy consumption after two decades of trying. Meanwhile, according to the Office for Budget Responsibility, subsidies for renewables were expected to cost £12 billion in 2021/22. This actually understates the reality because it does not include all of the indirect costs involved in grid balancing and so on, meaning the true cost is probably over £15 billion.

It is of course true that the recent rocketing of gas prices has reset the agenda. But it is important to note that the current price does not reflect the cost of extracting gas. It is the result of an imbalance in supply and demand. Such imbalances have occurred before, and a normally functioning market would quickly increase gas production, driving prices back down to historic levels.

But even before those price rises, it was being claimed that wind and solar power were cheaper than fossil fuel. However such claims fail to take into account the additional system costs imposed by their intermittency.

Moreover, claims that offshore wind costs are now down to around £40/MWh simply are not supported by the evidence. The claims are derived from the prices agreed for Contracts for Difference, the government subsidy mechanism. However, wind farms are under no legal obligation to actually take up these contracts; they are effectively only options.

Detailed examination of actual company accounts continues to show that the capital costs for building offshore wind farms has not fallen significantly in recent years, and that the true running costs are probably around £100/MWh. To put this into perspective, historically wholesale electricity prices have been under £50/MWh.

Solar power has certainly come down in cost in recent years, but the technology is a dead end here in the UK, because of our latitude. In winter, when demand for electricity is at its highest, our solar farms typically work at only 2% of their capacity.

Solar power certainly has a future in sunnier climates. But even in India, for instance, the government have realised that they cannot run an electricity grid purely on intermittent power. Even their ambitious plans only project that a 11% of their energy will be coming from wind and solar by 2040.

And it is of course intermittency which is the overriding problem here. You can forget about batteries and other forms of storage, as these can typically only supply power for an hour or two. This is useless when the wind stops blowing for days and weeks on end.

Hydrogen is usually wheeled out as the answer to all of our problems, replacing gas needed to back up wind farms as well as heat our homes. However, even the Committee on Climate Change accept that most of the bulk of our hydrogen will have to be made by steam reforming natural gas.

This process is not only expensive, it also wastes a lot of the gas input. In other words, you need more gas to produce hydrogen than you would need if you just burnt the gas itself in the first place. Worse still, steam reforming emits carbon dioxide, so you need to bolt on a carbon capture system adding yet more cost.

All in all, hydrogen made this way would be double the cost of gas in energy terms. But, crucially, you would still need as much natural gas as you do now, and more. Far from replacing fossil fuels, hydrogen increases our reliance on them.

The alternative is green hydrogen, which is made by electrolysis. It is usually suggested that surplus wind power is used for this. However, the amounts of hydrogen which could be produced this way would be tiny, as well as extremely costly given the intermittency of the process.

The bottom line is that we will still need gas, and lots of it, to back up a renewable heavy grid. Indeed, the more renewable capacity we build, the more backup we need.

And that is only considering electricity. We need lots more gas for heating and industrial use.

The biggest problem with using hydrogen, or for that matter electricity, for domestic heating is how you cope with peak demand in winter. On average over the year, demand for gas is roughly double that for electricity. But in winter, peak gas demand is seven times as much.

To get a scale of the numbers, gas consumption peaks at around 350 GW in mid winter. Current government plans target wind capacity of 45 GW by 2035, which on average will produce just 15 GW, and often as little as 2 GW.

You can of course store gas very easily, so that it can be turned on and off when needed. Green hydrogen, most of which would be made during summer when demand for electricity is low, would have to be stored for use in winter, something for which there is no ready solution.

There are plenty of vested interests out there who are claim hydrogen is the way forward and call for government “investment”. But what they are really after are the fat subsidies that will come with it.

The simple reality is that we will continue to need fossil fuels for many years to come. In the long term we will have look to develop new technologies such as nuclear fusion, or build small nuclear reactors and the like if we want to decarbonise.

Renewable energy has a part to play, but it can never be the whole answer.

[obligatory disclaimers sprinkled throughout ha~cr]

The findings do not counter the established science of climate change but highlight how the accounting of the amount of carbon withdrawn by plants and returned by soil is not accurate.

Peer-Reviewed Publication

VIRGINIA TECH

Virginia Tech researchers, in collaboration with Pacific Northwest National Laboratory, have discovered that key parts of the global carbon cycle used to track movement of carbon dioxide in the environment are not correct, which could significantly alter conventional carbon cycle models.

The estimate of how much carbon dioxide plants pull from the atmosphere is critical to accurately monitor and predict the amount of climate-changing gasses in the atmosphere. This finding has the potential to change predictions for climate change, though it is unclear at this juncture if the mismatch will result in more or less carbon dioxide being accounted for in the environment.

“Either the amount of carbon coming out of the atmosphere from the plants is wrong or the amount coming out of the soil is wrong,” said Meredith Steele, an assistant professor in the School of Plant and Environmental Sciences in the College of Agriculture and Life Sciences, whose Ph.D. student at the time, Jinshi Jian, led the research team. The findings are to be published Friday in Nature Communications.

“We are not challenging the well-established climate change science, but we should be able to account for all carbon in the ecosystem and currently cannot,” she said. “What we found is that the models of the ecosystem’s response to climate change need updating.”

Jian and Steele’s work focuses on carbon cycling and how plants and soil remove and return carbon dioxide in the atmosphere.

To understand how carbon affects the ecosystems on Earth, it’s important to know exactly where all the carbon is going. This process, called carbon accounting, says how much carbon is going where, how much is in each of Earth’s carbon pools of the oceans, atmosphere, land, and living things.

For decades, researchers have been trying to get an accurate accounting of where our carbon is and where it is going. Virginia Tech and Pacific Northwest National Laboratory researchers focused on the carbon dioxide that gets drawn out of the atmosphere by plants through photosynthesis.

When animals eat plants, the carbon moves into the terrestrial ecosystem. It then moves into the soil or to animals. And a large amount of carbon is also exhaled — or respirated — back into the atmosphere.

This carbon dioxide that’s coming in and going out is essential for balancing the amount of carbon in the atmosphere, which contributes to climate change and storing carbon long-term.

However, Virginia Tech researchers discovered that when using the accepted numbers for soil respiration, that number in the carbon cycling models is no longer balanced.

“Photosynthesis and respiration are the driving forces of the carbon cycle, however the total annual sum of each of these at the global scale has been elusive to measure,” said Lisa Welp, an associate professor of earth, atmospheric, and planetary sciences at Purdue University, who is familiar with the work but was not part of the research. “The authors’ attempts to reconcile these global estimates from different communities show us that they are not entirely self-consistent and there is more to learn about these fundamental processes on the planet.”

What Jian and Steele, along with the rest of the team, found is that by using the gross primary productivity of carbon dioxide’s accepted number of 120 petagrams — each petagram is a billion metric tons — the amount of carbon coming out through soil respiration should be in the neighborhood of 65 petagrams.

By analyzing multiple fluxes, the amount of carbon exchanged between Earth’s carbon pools of the oceans, atmosphere, land, and living things, the researchers discovered that the amount of carbon soil respiration coming out of the soil is about 95 petagrams. The gross primary productivity should be around 147. For scale, the difference between the currently accepted amount of 120 petagrams and this is estimate is about three times the global fossil fuel emissions each year.

According to the researchers, there are two possibilities for this. The first is that the remote sensing approach may be underestimating gross primary production. The other is the upscaling of soil respiration measurements, which could be overestimating the amount of carbon returned to the atmosphere. Whether this misestimate is a positive or negative thing for the scientifically proven challenge of climate change is what needs to be examined next, Steele said.

The next step for the research is to determine which part of the global carbon cycling model is being under or overestimated.

By having accurate accounting of the carbon and where it is in the ecosystem, better predictions and models will be possible to accurately judge these ecosystems’ response to climate change, said Jian, who began this research as a Ph.D. student at Virginia Tech and is now at Northwest A&F University in China.

“If we think back to how the world was when we were young, the climate has changed,” Jian said. “We have more extreme weather events. This study should improve the models we used for carbon cycling and provide better predictions of what the climate will look like in the future.”

As Steele’s first Ph.D. student at Virginia Tech, a portion of Steele’s startup fund went to support Jian’s graduate research. Jian, fascinated with data science, databases, and soil respiration, was working on another part of his dissertation when he stumbled across something that didn’t quite add up.

Jian was researching how to take small, localized carbon measurements from across the globe. While researching this, Jian discovered that the best estimates didn’t match up if all the fluxes of global carbon accounting were put together.

The research was funded by Steele’s startup fund from the College of Agriculture and Life Sciences at Virginia Tech and further supported by Pacific Northwest National Laboratory.

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JOURNAL

Nature Communications

DOI

10.1038/s41467-022-29391-5 

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Historically inconsistent productivity and respiration fluxes in the global terrestrial carbon cycle

ARTICLE PUBLICATION DATE

1-Apr-2022

From EurekAlert!

 The H2 Clipper also boasts a massive cargo volume capacity of over 265,000 cubic feet (7,500 cubic meters), which is “8 to 10 times more cargo space than any other air freighter”.

Sounds highly promising and thus may be a great example of an effective and even impressive way to put green energies to use.