W. S. Jevons (1865) on Waterpower, Biomass, and Geothermal (Memo to Obama, Part II)

W. S. Jevons in his early day recognized a central problem of windpower for powering machinery–intermittency. The wind does not always blow, and it cannot be known when this will occur, making an even flow of power (as from conventional sources) impossible short of cost-prohibitive battery backup.

What about the other renewables of the day: water power, biomass, and geothermal? 

Hydropower

Jevons identified several problems with falling water, or what is known today in electricity generation as hydropower. There can be too much flowing water to disrupt its application, water flow is seasonal, there can be “failure by drought,” and flat terrain limits water’s use as energy. As Jevons states in The Coal Question (London: Macmillan and Co., 1865), p. 129:

When an abundant natural fall of water is at hand, nothing can be cheaper or better than water power. But everything depends upon local circumstances. The occasional mountain torrent is simply destructive. Many streams and rivers only contain sufficient water half the year round and costly reservoirs alone could keep up the summer supply. In flat countries no engineering art could procure any considerable supply of natural water power, and in very few places do we find water power free from occasional failure by drought.

Another problem: water (as other renewables) is a flow of potential energy is not a store of energy that can be transported to where it is needed. It must be used where it originates. Jevons explains (ibid.):

The necessity … of carrying the work to the power, not the power to the work, is a disadvantage in water power, and wholly prevents that concentration of works in one neighbourhood which is highly advantageous to the perfection of our mechanical system. Even the cost of conveying materials often overbalances the cheapness of water power

And, finally, there is the capital cost of converting water into energy. Jevons states (ibid.):

Even the cost of conveying materials often overbalances the cheapness of water power

So falling water, in addition to windpower, cannot reliably or economically power industrial society. What about biomass and geothermal, the other renewables?  Jevons explains why neither breaks the renewables quandary to meet the energy needs of the machine age.

Biomass

The most dominant energy of mankind prior to the hydrocarbon energy age was what is today called primitive biomass, or the burning of plants and wood. Jevons, however, knew that the machines of the industrial age could not replace “nonrenewable” coal for primitive biomass (The Coal Question, p. 140):

We cannot revert to timber fuel, for ‘nearly the entire surface of our island would be required to grow timber sufficient for the consumption of the iron manufacture alone.’

Geothermal

And, finally, geothermal was a limited source given technological constraints (The Coal Question, p. 120–21):

The internal heat of the earth … presents an immense store of force, but, being manifested only in the hot-spring, the volcano, or the warm mine, it is evidently not available.