Waking  

Solar, Wind /

the Storage and Supply of Energy.


About ten years ago I told different people about news I had heard about the new wind power project at Bonneville. It was reported that the new Bonneville wind project was now the least costly of all new U.S. electrical power generation installations.
Capital costs were a little less than $2.00 per watt. Gas combustion turbines were a little over $2.00 per watt.

(In less than ten years the costs for both technologies dropped more by about one-third to one-half.) No one believed the facts on their face.

Those who did believe that it might be true had some way of explaining it away. They said it was only possible because of the grants and tax breaks and that it could not be economical and practical otherwise because of the basic high costs, high failures rate and inadequate wind. They all were mistaken in all of these things. Some of what they said were “Wind power works because the government gives money in grants or tax gifts. The low costs and high benefits statements are based on gimmicks and not the actual machines, installations and output. “There is not enough wind to produce enough energy to make it pay for individual installations or for the area or nation as a whole. “Wind machines are so unreliable that they require too much maintenance and keep failing.” None of those things were true. None of these things are true now. About ten years later I was talking with a generally informed person who was particularly interested in wind power. He still believed most of the same basic ten year old errors. By that time, ten years after the Bonneville project, he had a lot of information from the normal sources such as the Wall Street Journal.

He believed that getting wind power from all of those potential wind farms in the Mid West was impractical because the government and taxpayers wouldn’t come up with the money needed to build the facilities and transmission structure. (T Boone Pickens was saying at the time that he had a group of private investors who were lining up to pay the costs.) I spoke with an engineer from the Alameda Municipal Power last Spring and she said expressed many of the same ideas ideas about why wind power (and solar power) is not practical. "Long distance transmission is impractical because of the losses from resistance.

“There isn’t enough wind and solar resources to be worthwhile. “Electricity can not be stored. That it must be used up as it is generated. “We don’t have the technology to store enough electricity as needed. “Wind and solar are subject to abrupt fluctuations due to drops in wind or cloud cover blocking the sun and that the surges and drops can not be adequately managed. “Because of the intermittent generation, solar and wind can not satisfy the need for dependable “base line power” as is provided by fossil fuels, hydro power, geothermal and nuclear generation.”
A few years ago I attended a meeting on photo electric power generation sponsored by the Alameda Municipal Power utility. A senior engineer explained why AMP couldn’t have individual generators producing more power than they use at the time of generation. Practically none of things he said, which all these other people also seem too believe,   were actually so or made any sense. Those that are true in strict sense don’t make any sense in application.     Yet nearly everyone, including those who are particularly interested and even who are working and are responsible in the technical fields, seem uninformed or mistaken. The idea that electricity can not be stored is as silly as it is commonplace. Electricity can be stored. It has been known and been done for about two hundred years. The devices which store electricity are called “capacitors”. Work is being done to try to create capacitors capable of storing the amount of electricity needed for practical large energy supply. However, in a practical sense, electricity can not now be stored. But that does matter in a practical sense. It isn’t electricity which must be stored, it is energy. Automotive storage batteries do not store electricity, they store energy in the form of chemicals which take up and release electricity by converting it to and from different chemical forms. There are many ways to store energy. Flywheels store kinetic energy. Reservoirs above hydro power plants store potential energy. Stoage batteries store chemical energy. Compressed gases such as air and carbon dioxide store potential energy.

Energy can be stored as heat. Storage of energy as heat is old, well known, inexpensive and practical technology. It can be done on a small or on a large scale. I calculated the volume of granite rock rubble which would be required to meet the needs of the City of Alameda – populations about 70,000. I assumed the heat needed to run heat engines such as steam engines could be stored and used between 600 F and 500 F and that the loss of energy from converting heat to electricity would be about twenty percent (that is about right at those temperatures). If so, a volume equivalent a few square city blocks area one hundred feet deep would hold enough energy to supply as much electricity as was supplied by the Alameda utility for the entire year of 2007. In other words, all the energy which Alameda could use for electricity could be stored cheaply in one very small valley. People say, “But we don’t have small valleys in Alameda.” Of course we don’t. But there are many small valleys near by. There would be storage areas near the collector / generator facilities and there would be the same transmission lines we have now. Regarding the problem of using the electricity as it is generated, the peak generation time of Alameda is in the afternoon, exactly at the time that people in nearby communities are scrambling for electricity to run their air conditioners. There are the problems of the drops and surges in electrical generation   because the drops and starts and clouds may cover the sun. Instead of placing the burden on the grid operators for smoothing out the supply, the major burden should be placed on the generators. They can operate individually or in cooperative groups to manage the supply to the grids. They can balance the output of the various generators in the area network and can use of flywheels, chemical batteries, capacitors, compressed gases and heat storage as well. It is said that wind and solar can not meet the needs for “base-line demand” which is now met by fossil fuels, hydro-power and nuclear generation. But heat energy storage is very practical and entirely capable of smoothing out the solar and wind generation to provide base line energy supply. The problem of the high energy losses from the long distance transmission of standard voltage AC electricity has been solved. Long distance efficient high voltage DC transmission systems are now practical and operating. One transmission system from Montana and  Wyoming to Southern California and Arizona is now being built. Others are planned and being built. There are far more wind power projects waiting than there is transmission capability. "Currently almost 300,000 thousand mega watts of wind projects, more than enough to 20 per cent of (U.S.) electricity needs, are waiting in  line to connect to the grid because there is inadequate transmission capacity to carry the electricity."
(The AWEA and EIA year 2009 report.)

The major problem is the red tape required for the permits. It takes about five years to go through the red tape and about two years to build the lines.

Here is a background discussion on the economic practicality of wind and solar generation with long distance transmission. A few years ago our electric utility was hoping to buy energy from the geo thermal project for nine and a fraction cents per kWh. We didn’t get the contract and our utility was very disappointed. At the same time, the Sacramento Municipal Utility District reported producing electricity from its wind farm at a cost of about four and one-half cents per kWh. I heard recently that wind power contracts are currently being settled at costs of about six cents per kWh. My rough estimate is that the cost of transmission of electricity from cheap wind generators in Montana to Southern California would be less than two cents per kWh including capital costs for planning and construction, operation, maintenance and profit. I hear that the average cost nationwide of new electricity is about twenty cents per kWh, with the costs for some utilities ranging above fifty cents. When I talk with ordinary interested folk, including responsible professionals working in the field, they don’t know most of this stuff. They haven’t even heard of much of it. They seem mistaken about much of what they do know and have actually heard. See my table below for calculations of costs of long distance transmission   HV DC Trasmission costs ken peterson February 28. 2012 based on Green Manufacturer Nov/Dec 2011 Sage Supplier  pg 14 Transwest Express will be a $ 3 billion carrying 600 kV, 725 mile long from Wyoming to So. Calif. Arizona, Nevada, Colorado and Utah. Assume capacity of 3,000 mW   (500 kV gives 2,040 mW; 765 kV gives 5,000 mW) One Year Cost kWh $0.114 per kWh
 Ten year Cost / kWh $0.011 per kWh


(To one point one cents allow and added cost of nine tenths of a cent for operation and maintenance and profit..That may be high ).