"If you keep on saying certain green energy forms aren't viable...

"If you keep on saying certain green energy forms aren't viable from an economic point of view, what price are you putting on our environment?"

That's a totally false premise because it implies that anyone who invokes economic considerations in discussion of renewable energy is happy to harm the environment.

By way of analogy, everyone would like to see a discovery made for a cure for cancer, but that doesn't mean no one should be able to question the economic merits of any of the many research programs being conducted in an attempt to find a cure for cancer.

Just about everything human beings do comes at some kind of environmental cost. Some people simply elect to not lose money in the process.

And don't for a minute think that the environmental cost to developing renewables is anywhere close to zero.

As will be show below, renewable energy manufacture is very energy intensive process, and the energy predominantly used is of the bad kind.

So it's not only the financial economics that I question, but it is also the environmental economics of rolling out renewables that warrant questioning, I think.

The financial economics have been discussed at length so I'll just sum up the salient outcomes based on the world's leading states (Germany, Spain and California) when it comes to rolling out renewables:

After trillions of dollars spent on renewable energy and storage in those states, renewable energy satisfies all the points on the demand curve between 5% and 8% of the time. (Recall the Share of Demand vs Proportion of Time graphs which were contained in a previous post - which was cancelled for being off-topic despite it being no different in tone and content to just about all the other posts on this thread, so probably because there is just certain factual evidence that some people would prefer to not be seen:



Remember that it doesn't matter how large you make the area under the energy supply curve (i.e., add more renewable capacity), it is to no avail if it fails to satisfy all points on the demand curve. In essence, the physics of intermittency. And spending more and more money adding more and more intermittent energy merely increases the area of the supply curve, but doesn't address the intermittency problem. Cold, hard laws of Physics.

That's the nub of the financial economics problem; so let's now turn to the environmental economics of renewables.

Affluent Westerners get a warm, fuzzy feeling helping the climate by putting solar panels on their roofs, by placing an order with a mere click of a mouse on their computers in the comfort of their living rooms. Yet they have zero idea of the process involved in making those solar panels which, after all, have a finite life.

Take just the polysilicon, the critical compound contained in solar panels. I'll wager London to a brick that very few people know of the genesis of polysilicon and the process by which it is made. Hint: Silicon dioxide (i.e., the sand from which polysilicon is made) has a high melting temperature of close to 1,800 degrees Celsius which, combined with energy requirements for the reductants and fluxes, a furnace temperatures of over 2,000 degrees are required. That's just the first step in the Siemens Process; then it still has to go through a hydrochloric acid wash and re-heated to create silicon vapour which is gets distilled into high-purity silicon. Then it needs to have boron added and cast into ingots. After that it is wire-sawn into think wafers.

Just to make the polysilicon - forget about anything else - is a very energy-intensive process:
It requires 4,000 kWh of energy to manufacture 1kW of Solar Power which, at Solar's capacity factor of around 0.20 equates to 0.15kW.


So the payback period is 4,000kWh divided by 0.12 = 26,700 hours, i.e., 3 year energy payback. And that's just for the solar panel itself, not excluding its transportation and installation that will easily be equal to another few thousand kWh. So we are talking about a 4 or 5 year energy payback time (EPT) from solar

This crude estimate is within the range of many independent, peer-reviewed studies, for example in the EPB range (admittedly wide) estimated by Aman, M, et al (https://doi.org/10.1016/j.rser.2014.08.086) .

But the EPT for solar is of a similar order of magnitude to that of coal, gas and even nuclear power, which are around 3 years:


(Source: Aman, M, et al)

So don't for a minute thing that your nice new shiny solar panels are not environmentally innocent; it requires a lot of energy to bring them into existence.

And where does that required energy come from?

Well, over 90% of it comes from China, specifically from Xinjang province.
And why Xinjang province, one might ask?

Well, because Xinjiang province hosts a disproportionate share of China's coal reserves and is home to a large percentage of China's coal fired power capacity. Coal fired power which is used to manufacture over 90% of the polysilicon used in the world's solar panels.

Therefore, when it comes to putting a price on the environment, bringing renewable energy hardware into existence does its fair share of harm to the environment.

Just because you, and other blinkered advocates of renewable energy can't see the environment cost being paid, doesn't mean it doesn't exist.

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