The Fundamental Limitations of Renewable Energy

The Fundamental Limitations of Renewable Energy

Posted on theenergycollective by Schalk Cloete

Schalk Cloete begins:

Many people still think that it will not be long before renewable energy such as solar and wind becomes outright cheaper than fossil fuels, thereby leading to a rapid expansion of the thin orange slither in the graph below. This is an ideologically very attractive notion, but, as discussed in this article, it is questionable whether this is in fact physically possible.

World Consumption: Millions tonnes oil equivalent

Schalk Cloete then asks:

So, what does renewable energy have to accomplish before it can compete with fossil fuels in an open market? Well, in short, we will have to overcome the diffuse and intermittent nature of renewable energy more efficiently than we can overcome the declining reserve qualities and unrefined nature of fossil fuels.
In other words, renewables need to overcome the following two challenges in order to displace fossil fuels in a fair market:
  1. Solar panels and wind turbines need to become cheaper than raw fossil fuels. This is the challenge posed by the diffuse nature of renewables.
  2. Storage solutions need to become cheaper than fossil fuel refineries (e.g. power plants). This is the challenge posed by the intermittent nature of renewables.
He then says that renewables, if they are going to compete in an open market, technology has to advances to cover the above two points.

He mentions that the Earth is surrounded by incredible amounts of diffuse energy like solar radiation and wind but says "this energy is useless to us unless it is concentrated into forms such as electricity or fuels."
The reason behind this is called the second law of thermodynamics which states that energy must flow from a concentrated form to a more diffuse form in order to do work.
On the intermittent nature of renewables Cloete says:
If intermittent renewables like solar and wind are ever to contribute a sizable portion of our global energy mix, a large amount of additional infrastructure will need to be deployed in order to counter the large fluctuations in output varying over timescales ranging from seconds to years.

Final word

So, these are the facts. In order for intermittent renewable energy sources such as solar PV to effectively compete with fossil fuels like coal, both the price of installed solar panels and the price of battery storage will need to reduce by a full order of magnitude. In addition, optimistic long-term projections state that both solar panels and battery storage will reach technological maturity at roughly triple the cost of their fossil fuel counterparts.
Read the whole item at The Energy Collective - Link.

Authored by:   Schalk Cloete 
 I am a research scientist searching for the objective reality about the longer-term sustainability of industrialized human civilization on planet Earth. Issues surrounding energy and climate are of central importance in this sustainability picture and I therefore seek to learn more from the Energy Collective community.