Tag: energy

Entropy


It seems you can’t talk about entropy without mentioning the second law of thermodynamics. That law states that the total entropy of an isolated system can never decrease over time. This creates the asymmetry between the past and the future, the irreversibility of natural processes and the arrow of time. It is entropy that ensures that, on the macroscopic scale, time can only pass in one direction — from a state of lower entropy to one of higher entropy.

This is often simplified to define entropy as the increase in disorder with time. This is particularly favored by creationists who latch onto their own simplified version of the second law to convince themselves that evolution is impossible. Their version of the second law, usually stated something like, “Disorder increases over time,” assures them that a supernatural power is required to support life and evolution. Coupled with their mistaken belief that evolution is a force for directed improvement, this explains some of the crazy things they say.

Can you see where they went wrong in appealing to the second law? That’s right. They left out the part about where it applies to an isolated system. An open system, such as the Earth, can receive energy from an outside source, like the sun. Under those conditions the total entropy on Earth can certainly decrease, but only because the total entropy of the Earth-sun system is increasing as the sun dissipates its energy. Their other mistake is to misinterpret “can never decrease” as “always increases.” This whole process of misunderstanding and misinterpreting and misusing the second law is unironically a very good demonstration of entropy, which can never decrease in a closed mind.

The reason entropy is linked to thermodynamics is that it started out as a description of waste heat or energy loss in steam engines and other mechanical devices. Such things are never 100% efficient at turning energy into work, and the people working on the problem needed a term for their bookkeeping. It was only later as we understood more about the physics underlying thermodynamics that other definitions, such as “disorder,” evolved. It also applies to the dispersal of concentrated energy, and even the dispersal of particles.

Another way to define entropy is as the amount of energy (usually thermal energy) in a closed system that is unavailable to do work. You can have a lot of energy in a closed system — a boiler, for instance — but if the energy is evenly distributed throughout the system, then there’s no way you can get it to do work within the closed system. Therefore it has high entropy. The only way to get work out of it is to pair it up with an external system that is at a different energy level, and then tap into the energy that is transferred between them as they seek equilibrium.

Here is one more way to think of entropy. When a system is in a configuration that has few ways for its parts to be arranged, it has low entropy. A configuration that has many possible arrangements has high entropy. So a glass of water that has an ice cube in it has lower entropy than the glass of water after the ice cube has melted. In the first, all the coldest water is in the ice cube — fewer ways to do that, lower entropy. In the second, all the water is evenly distributed at the same temperature — more ways to do that, higher entropy.

So, entropy is inexorably increasing in the universe overall. It can decrease locally under the right conditions, but only at the expense of a greater increase elsewhere. It doesn’t prevent evolution, which actually depends on increasing entropy. It is entropy that tells us which way time flows — from low to high.

rjb

10% of Fossil Fuel Subsidy ‘Could Pay for Green Transition’

via Just 10% of fossil fuel subsidy cash ‘could pay for green transition’ | Environment | The Guardian

In the global energy market, renewables get about U$100 billion per year in subsidies. Fossil fuels get U$370 billion per year. Subsidies are defined as direct financial or more indirect tax support for purchasers or producers. It has been estimated that diverting from 10 – 30% of the fossil fuel subsidies to renewables would pay for a rapid transition to clean(er) energy.

From the Guardian:

Switching just some of the huge subsidies supporting fossil fuels to renewables would unleash a runaway clean energy revolution, according to a new report, significantly cutting the carbon emissions that are driving the climate crisis.

Coal, oil and gas get more than $370bn (£305bn) a year in support, compared with $100bn for renewables, the International Institute for Sustainable Development (IISD) report found. Just 10-30% of the fossil fuel subsidies would pay for a global transition to clean energy, the IISD said.

To quote Richard Bridle of the International Institute for Sustainable Development:

“Almost everywhere, renewables are so close to being competitive that [a 10-30% subsidy swap] tips the balance, and turns them from a technology that is slowly growing to one that is instantly the most viable and can replace really large amounts of generation,” said Richard Bridle of the IISD. “It goes from being marginal to an absolute no-brainer.”

It will help us reach our climate protection goals and reduce pollution.

“Taking away subsidies from fossil fuels and channelling them towards clean energy would boost their development at a much faster pace, and help secure our climate goals,” said Ipek Gençsü of the Overseas Development Institute. An added bonus is the social and economic benefits, such as reduced air pollution and health spending, she said.

The cost goes up if we include indirect subsidies. Yes, that’s U$5.2 trillion.

The IMF also includes the cost of the damage fossil fuel burning causes to climate and health, leading to an estimate of $5.2tn of fossil fuel subsidies in 2017, or $10m a minute. Ending the subsidies would cut global emissions by about a quarter, the IMF estimates, and halve the number of early deaths from fossil fuel air pollution.

You can find the full article at the Guardian’s website. They might ask you for a donation, but they’ll let you look whether you choose to make one or not.

via Just 10% of fossil fuel subsidy cash ‘could pay for green transition’ | Environment | The Guardian

rjb

Fossil Fuel Subsidies Cost $5 Trillion Annually

They keep telling us that alternatives to fossil energy are too expensive. That we shouldn’t be subsidizing the alternatives because it creates an uneven playing field. They tell us that the alternatives should compete on merit, just like the fossil energy industries do, and stop looking for government handouts. I think we should go the other way and subsidize the competition to the same level we already have been subsidizing the incumbent. With that kind of money, I foresee rapid advancements in new technology. – rjb

Global energy subsidies, including the social and environmental costs associated with heavily subsidized fossil fuels, are costing the world’s governments upward of $5 trillion annually, according to new estimates released yesterday by the International Monetary Fund.

Source: Fossil Fuel Subsidies Cost $5 Trillion Annually and Worsen Pollution – Scientific American

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