Renewable Energy’s Inconvenient Truth

By Paul Homewood

 

h/t Ian.mpp

 

A detailed critique of renewable energy in OilPrice.com:

 

 

 

The energy needs of the world’s economy seem to be easy to model. Energy consumption is measured in a variety of different ways including kilowatt-hours, barrels of oil equivalent, British thermal units, kilocalories and joules. Two types of energy are equivalent if they produce the same number of units of energy, right?

For example, xkcd’s modeler Randall Munroe explains the benefit of renewable energy in this video. He tells us that based on his model, solar, if scaled up to ridiculous levels, can provide enough renewable energy for ourselves and a half-dozen of our neighbors. Wind, if scaled up to absurd levels, can provide enough renewable energy for ourselves and a dozen of our neighbors.

There is a major catch to this analysis, however. The kinds of energy produced by wind and solar are not the kinds of energy that the economy needs. Wind and solar produce intermittent electricity available only at specific times and places. What the world economy needs is a variety of different energy types that match the energy requirements of the many devices in place in the world today. This energy needs to be transported to the right place and saved for the right time of day and the right time of year. There may even be a need to store this energy from year-to-year, because of possible droughts.

I think of the situation as being analogous to researchers deciding that it would be helpful or more efficient if humans could change their diets to 100 percent grass in the next 20 years. Grass is a form of energy product, but it is not the energy product that humans normally consume. It doesn’t seem to be toxic to humans in small quantities. It seems to grow quite well. Switching to the use of grass for food would seem to be beneficial from a CO2 perspective. The fact that humans have not evolved to eat grass is similar to the fact that the manufacturing and transport sectors of today’s economy have not developed around the use of intermittent electricity from wind and solar.

Substituting Grass for Food Might “Work,” but It Would Require Whole New Systems

If we consider other species, we find that animals with four stomachs can, in fact, live quite well on a diet of grass. These animals often have teeth that grow continuously because the silica in grass tends to wear down their teeth. If we could just get around these little details, we might be able to make the change. We would probably need to grow extra stomachs and add continuously growing teeth. Other adjustments might also be needed, such as a smaller brain. This would especially be the case if a grass-only diet is inadequate to support today’s brain growth and activity.

The problem with nearly all energy analyses today is that they use narrow boundaries. They look at only a small piece of the problem–generally the cost (or “energy cost”) of the devices themselves–and assume that this is the only cost involved in a change. In fact, researchers need to recognize that whole new systems may be required, analogous to the extra stomachs and ever-growing teeth. The issue is sometimes described as the need to have “wide boundaries” in analyses.

If the xkcd analysis netted out the indirect energy costs of the system, including energy related to all of the newly required systems, the results of the analysis would likely change considerably. The combined ability of wind and solar to power both one’s own home and those of a dozen and a half neighbors would likely disappear. Way too much of the output of the renewable system would be used to make the equivalent of extra stomachs and ever-growing teeth for the system to work. The world economy might not work as in the past, either, if the equivalent of the brain needs to be smaller.

 

Full article here.

 

Normally this is all so obvious, it should not need saying. Unfortunately so much of our media have become so beguiled by renewable energy, that they have forgotten to ask the obvious questions.