Tom Shepstone
Shepstone Management Company, Inc.

Like wind, solar energy, is a nice supplemental source but proposed solar energy solutions as alternatives to natural gas are less than half-baked ideas.

Three days ago I offered up a post pointing out the foolishness connected with wind energy as an alternative to natural gas. Wind energy can serve as a supplemental source of power but it makes no sense in competition with natural gas and is simply another utopian scheme propped up by a web of corporate and government cronyism. I noted wind energy’s capacity factor, at roughly one-third of theoretical generation capacity, is only about half what a combined cycle natural gas plant will deliver, according to EIA but it turns out solar energy solutions are even more misguided if one looks deeper into the capacity factors.

What I’m referring to are some new numbers from the Energy Information Administration (EIA) that look at capacity factors for different energy sources across the world. There are many considerations that go into these calculations. Old gas plants are analyzed together with new combined cycle plants operate at more than twice the efficiency, for example. Also, “because natural gas and petroleum prices are typically higher than coal prices in most regions, plants using natural gas or petroleum are typically operated to meet loads during periods of peak and intermediate demand for electricity” so those numbers are often artificially lower than they could be.

Similar issues can affect some renewables, but, of course, the chief factor in those cases is the fact there are times when the sun doesn’t shine and the wind doesn’t blow. Solar, in particular, is heavily burdened by this limitation. The following chart, prepared from the EIA data, compares solar energy solutions with natural gas and the results are absolutely stark:

No further evidence is needed to demonstrate solar energy is strictly a supplemental; it can begin to carry the load the way gas does (and this is with massive governmental pushes and subsidies to encourage artificially high use of solar.

Still more evidence can be found at Watts Up With That as two authors have some fun explaining just what solar energy solutions would be required to satisfy all our future US electricity demands:

• The generating power will need to be at least 1,100 gW or 1.1 TW and the battery capacity will need to be 4,400 gWh to allow for the efficiency losses and the plant margin.
• To generate the system requirements of 1,100 gW, a fixed solar array would have to have an area of 1,100,000,000,000/37.5 sq meters, made up from 29.333 billion, 1 meter square panels, covering an area of 29,333 km2 or a square with sides of 171.3 km long. This is about the size of Belgium and 50% bigger than Israel, just for the silicon PV cells. Using the more expensive tracking array could reduce this area to 22,000 km2 or a square with sides of 148.3 km.
• If 1 square metre PV panels were manufactured at the rate of 1 per second, it would take 930 years to manufacture 29.3 billion panels.
• It takes energy to make PV panels, especially the highly efficient, old-school crystalline silicon kind. A study by researchers from the Netherlands and the USA (Fthenakis, Kim and Alsema, 2008), which analyses PV module production processes based on data from 2004-2006 finds that it takes 250kWh of electricity to produce 1m2 of crystalline silicon PV panel. The solar panels considered above typically produce around 300kWh electricity per year, so it will take almost a year to “pay back” the energy cost of the panel.
• The total area covered by the solar array will significantly larger than the area of the panels to allow for installation, maintenance access and periodic cleaning. The space required for the batteries is in addition to this. Currently, Lithium ion batteries suitable for grid storage are available from several suppliers in 40 foot containers with various energy storage capacities of around 1 mWh and costing $750,000 or more each. They usually include cooling and an electronic converter unit delivering AC power at 480 Volts 60 Hertz or similar. To store 1 mWh during a charging period of 12 hours, the average charging power must be 1mWh ÷ 12 = 83.33 kW. Similarly the battery must be capable of delivering a power of 83.33 kW during 12 hours of discharge.
• To store 4,400 gWh would require 4.4 million of these 40 foot containers costing $3,300,000,000,000 or $3.3 trillion. For 4.4 million containers, the containers would cover an area of 130.8 million m2 = 130.8 km2 or a square with sides 11.44 km long; but adequate access space must also be provided, adding substantially to the total.
• The biggest problem however comes from the finite life of the battery, since the entire installation will have to be replaced every 8 to 10 years.
• Unlike the situation with lead acid batteries, there are currently very few recycling plants able to recycle Lithium batteries to extract the useful chemicals. In any case, taking a Lithium Cobalt cell as an example, the Lithium content in the LiCoO2 cathode material is only 7% by weight. Lithium is between 20 and 100 times more abundant in the Earth’s crust in terms of the number of atoms than Lead and Nickel, so that the demand for recycling is less.
• If these 44 million containerized batteries were manufactured in China, it would take 587 round trips of twenty days each way on the largest container ships to deliver them to the USA.

Kind of puts things in perspective, doesn’t it? Solar energy, like wind, is only capable of being a secondary energy source with today’s technology. Could that change? Certainly, but in the meantime, the answer is an all-of-the-above strategy that uses them as a supplemental source of energy, which means partnering with gas, not fighting it.

German Solar Plant