Ten Reasons Intermittent Renewables (Wind and Solar PV) are a Problem

26 01 2014

Gail Tverberg

Gail Tverberg

raises many points that have already been posted here…..  I only reproduce her dot points one and nine, because they are the most relevant to DTM, but I recommend you read the entire article on her website if you have the time.  It is, as usual, an excellent well researched piece of journalism

Intermittent renewables–wind and solar photovoltaic panels–have been hailed as an answer to all our energy problems. Certainly, politicians need something to provide hope, especially in countries that are obviously losing their supply of oil, such as the United Kingdom. Unfortunately, the more I look into the situation, the less intermittent renewables have to offer.

1. It is doubtful that intermittent renewables actually reduce carbon dioxide emissions.

It is devilishly difficult to figure out whether on not any particular energy source has a favorable impact on carbon dioxide emissions. The obvious first way of looking at emissions is to look at the fuel burned on a day-to-day basis. Intermittent renewables don’t seem to burn fossil fuel on day-to-day basis, while those using fossil fuels do, so wind and solar PV seem to be the winners.

The catch is that there are many direct and indirect ways that fossil fuels come into play in making the devices that create the renewable energy and in their operation on the grid. The researcher must choose “boundaries” for any analysis. In a sense, we need our whole fossil fuel powered system of schools, roads, airports, hospitals, and electricity transmission lines to make any of type of energy product work, whether oil, natural gas, wind, or solar electric–but it is difficult to make boundaries wide enough to cover everything.

The exercise becomes one of trying to guess how much carbon emissions are saved by looking at tops of icebergs, given that the whole rest of the system is needed to support the new additions. The thing that makes the problem more difficult is the fact that intermittent renewables have more energy-related costs that are not easy to measure than fossil fuel powered energy does. For example, there may be land rental costs, salaries of consultants, and (higher) financing costs because of the front-ended nature of the investment. There are also costs for mitigating intermittency and extra long-distance grid connections.

Many intermittent renewables costs seem to be left out of CO2 analyses under the theory that, say, land rental doesn’t really use energy. But the payment for land rental means that the owner can now go and buy more “stuff,” so it acts to raise fossil fuel energy consumption.

Normally the cost of making an energy-related product gives an indication as to how much fossil fuel energy is involved in the process. A high-priced energy product gives an expectation of high fossil fuel use, since true renewable energy use is free. If the true source of renewable energy were only wind or solar, there would be no cost at all! The fact that wind and solar PV tends to be more expensive than other electricity generation gives an initial expectation that the fossil fuel energy requirements for creating this energy source are high, rather than low, if a wide boundary analysis were to be done.

There are some studies based on narrow boundary studies of various types (Energy Return on Energy Invested, Life Cycle Analysis, and Energy Payback Periods) that suggest that there are some savings (from the top of the icebergs) if intermittent renewables are used. But more broadly based studies show that the overall amount of fossil fuel energy used by intermittent renewables is really so high that we don’t come out ahead by its use. One such study is Weissbach et al.’s study in Energy called  Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants. Another is an analysis of Spanish installed solar power by Pedro Prieto and Charles Hall called Spain’s Photovoltaic Revolution: The Energy Return on Energy Invested.

I tend to use an even wider boundary approach: what happens to world CO2 emissions when we ramp up intermittent renewables? As far as I can tell, it tends to raise CO2 emissions. One way this happens is by ramping up China’s economy, through the additional business it generates in the making of wind turbines, solar panels, and the mining of rare earth minerals used in these devices. The benefit China gets from its renewable sales is leveraged several times, as it allows the country to build new homes, roads, and schools, and businesses to service the new manufacturing. In China, the vast majority of manufacturing is with coal.

china-energy-consumption-by-source

Another way intermittent renewables raise world CO2 emissions indirectly is by making the country using intermittent renewables less competitive in the world market-place, because the higher electricity cost raises the price of manufactured goods. This tends to send manufacturing to countries that use lower-priced energy sources for electricity, such as China.

A third way that intermittent renewables can raise world CO2 emissions relates to affordability. Consumers cannot afford high-priced electricity without their standards of living dropping. Governments may be pressured to change their overall electricity mix to include more very low-cost energy sources, such as lignite (a very low grade of coal), in their electricity mix to keep the  overall price in an affordable range. This seems to be at least part of the problem behind Germany’s difficulties with renewables.

If there is any savings at all in CO2 emissions, it would seem to be from inexpensive intermittent renewables–ones that don’t really need subsidies. If renewables need a subsidy or feed in tariff, a red danger light should be flashing. Somewhere the process is  using a lot of fossil fuels in its production.

9. My analysis indicates that the bottleneck we are reaching is not simply oil. Instead, a major problem is inadequate investment capital and too much debt.  Ramping up wind and solar PV tends to make those problems worse, not better.

As I described in my post Why EIA, IEA, and Randers’ 2052 Energy Forecasts are Wrong, we are reaching an investment capital and debt bottleneck, because of the higher extraction costs of oil. Adding intermittent renewables, in which huge costs are paid out in advance, adds to this problem. Because of this, ramping up intermittent renewables tends to make collapse come sooner, rather than later, to the countries trying to ramp up these energy sources.