Archive for the ‘electricity’ Category

Ethanol or Biomass to Electricity

Thursday, July 16th, 2009

One of the major reasons for increasing the use of biofuels is to reduce greenhouse gas emissions. The same can be said for switching to electric vehicles.

Recently in a study done by researchers at the University of California, Merced, an electric SUV was compared to a SUV using ethanol for fuel. The electric vehicle was powered by bioelectricity created with the same amount of switchgrass used to make the ethanol.

Well, the electric vehicle won, are you surprised? The SUV powered by bioelectricity could travel 14,000 miles on electricity created from an acre of switchgrass. The ethanol fueled internal combustion engine in the other SUV could travel 9,000 miles on the same amount of switchgrass. Eliot Campbell, one of the researchers explained, “the internal combustion engine just isn’t very efficient, especially when compared to electric vehicles.” “Even the best ethanol-producing technologies with hybrid vehicles aren’t enough to overcome this.” The researchers concluded that the obvious course is to convert biomass to electricity, rather than ethanol. This course of action would double the greenhouse gas offsets to bring about climate change. The researchers warn that the problem is more complex than this particular study covered. These results only cover the issues of transportation and climate. The problems of water consumption, air pollution and economic costs were not addressed. What is your take on the subject? Leave a comment and we’ll have a lively discussion about this or any other issue involving saving our environment. Let’s talk, see you around the galaxy…

Wind Turbines Offshore in Deep Water For The Northeast US

Wednesday, October 22nd, 2008

The state of New Jersey is helping to fund an initiative by Garden State Offshore Energy to build wind turbines 16 miles offshore. The state would like to have 3000 megawatts of wind power from offshore wind farms by the year 2020, which is 13 percent of the state’s electricity needs. The Garden State initiative will provide 350 megawatts of electrical power, and represent the US’s first deepwater wind turbines.

Proposed wind turbines in this country have been challenged diligently by the public and shipping interests and this has slowed or outright stopped some proposed offshore wind farms. With the deepwater turbines this is no longer a problem. When the turbines are closer in to shore they are visible and some feel eyesores. Shipping interests say shipping lanes are compromised by the wind turbines. The problem was that no wind farms were allowed any further out than 3-4 miles. The federal government has now agreed to open up deep ocean waters, and by new federal government rules this will create vast areas of space to place wind turbines. The area that they have agreed to let companies develop is the outer continental shelf, it extends to the edge of U.S. territory 230 miles out. These wind farms would not obstruct views, or interfere with any other activity.

The U.S. Department of the Interior, the agency that is responsible for the new rules planned to finalize to rules by the end of 2008. They will lease plots of the shelf to developers of wind farms and other renewable energy projects. These other projects include ocean current and wave-harvesting technologies. States along the northeast coast where 80 percent of the population of the U.S. lives, have decided to providing some of the funding for these wind farms in the hope that they will have some of the energy from the farms transmitted into state grids and help meet renewable energy requirements. The Ocean Renewable Energy Coalition’s founder Sean O’Neill thinks the leases may be too expensive and the environmental review process too extensive. Other groups are saying that there are too many barriers to overcome, and they want to know are these waters really open?

Opening the shelf is probably the only way to have offshore wind projects for the U.S. There have been problems in the past trying to get something like this done. Most proposed wind projects in state waters can be seen from shore, and there’s potential interference with shipping lanes. Wind turbines in these conditions have to have a smaller design and this leads to a reduction in the anticipated amount of electricity causing profits to fall. In addition no one seemed to know who had control, before the new federal government rules. As a result there is not a single offshore wind turbine operating in the U.S. today.

Nearly 80 percent of the population of the U.S. live in coastal states. In the heavily populated areas there is simply no room for wind turbine farms. Wind turbines located on the continental shelf will generate 1000 gigawatts of electricity. That number is more than the electrical capacity of the entire U.S. The U.S. is in the rear with regard to offshore wind turbines, Europe has more than 2 dozen wind parks in their waters.

New designs have to be developed for deep water wind turbines. At shallow depths it is a simple matter to drive a pole into the floor of the sea, this is called a monopile. The concept is like having to drive piles for reinforced concrete construction. Obviously they cannot have the deepwater turbines without new designs that will take the depth of the water into consideration.

Engineers and researchers are trying new designs like underwater tripods and lattice type structures called jackets. German developer Alpha Ventus is in the next few months going to build a dozen turbines with tripod and lattice structures in deep water. The leading developer in this type of technology are the engineering staff for Beatrice Wind Farm in the North Sea close to Scotland, with turbines 138 feet deep and over 15 miles from shore.

Engineers have determined these designs would be good for depths of 200 feet. The option they have for deeper water is floating structures used by the oil industry. The platforms would not be exactly the same as the oil industry has experience in using, however they would be very similar. Private developers in Europe say they are working on prototypes for this model. Otherwise this technology could take up to a decade to to get up and running.

The cost of deepwater windturbine installation is twice that of wind turbines on land. The industry here in the U.S. is being very careful, they don’t want to fail because of fear that would hamper or completely stop further offshore construction of wind turbine farms.

Nuclear Power Is Not A Renewable Energy Resource

Thursday, October 16th, 2008

There is quite a bit of talk about nuclear power as it is being touted as a clean reliable energy source. It is actually put on par with solutions to our power needs like solar and wind power. I beg to differ. The nuclear power industry is getting as old as I am! Nuclear plant owners are trying to see if they may be able to capitalize on these developments. They are doing retrofits and upgrades in every plant they can in order to spruce themselves up for the unwary public.

The problem as I stated earlier is the age of the nuclear plants currently in existence. Around 40 percent of U.S. nuclear power stations are over 30 years old. More than 90 percent of all plants in the U.S. are over 20 years old. Well, you might say, so what? If they are working out, then let’s use them. Therein lies the rub. Nuclear power plants are built using reinforced concrete and structural steel , with concrete having the higher numbers in so far as materials used are concerned.

Over time the materials used to build a plant start to corrode and develop cracks (known as stress corrosion cracking [SCC]) because of age and exposure to radiation. If you consider steam turbines then the blade attachment areas and disc bores of low pressure turbine rotors are in danger of SCC.

The owners of some plants want to replace low pressure steam paths with higher pressure steam flow equipment. This theoretically could result in higher output. The emphasis on theoretically is mine. I have worked in the nuclear power industry as an engineer and one thing is certain, and that is nothing is certain. It is hoped that this solution will address reliability issues with these existing steam turbines.

The retrofit that most are opting for would include installing new low pressure rotors, rotating and stationary blades, inner casings and blade carriers. The scope of this type of retrofit would be large and costly. They would have to install or replace: high efficiency, integrally shrouded, reaction type blading for their front stages; longer last stage rotating blades to reduce the energy content of the steam leaving the turbine, thereby increasing turbine output; provide consistent and predictable vibration characteristics, snubbers at three quarter height will need to interconnect the last stage rotating blades and the second to last stage blades will need to be linked by integral tip shrouding; provide reduced stage leakage due to better sealing and reaction characteristics over the length of the blade; and select materials to provide erosion corrosion characteristics.

These upgrades are not all that would need to be done, and I include them here to show the complexity of this proposed fix of the aging nuclear power plants. This is not to confuse the layman but merely to show that this undertaking would be of immense scope and would cost millions of dollars. Dollars perhaps better spent pursuing alternative energy in the form of renewable energy resources.

The owners of some of these plants are saying that by the low carbon output (i.e. lower CO2 which has been shown to cause global warming) and possible gains in capacity, they could in some cases identify around 350MW of electricity increase by 2014.

I don’t want to give the impression that nuclear power should be abandoned, I am a scientist and I would not make rash statements like this without some sort of research. It is simply obvious that we are already paying a very high price for electricity generated by nuclear power. The cost alone would be enough to deter some, and there is still the question of safety. Obviously we have not mastered nuclear power to the point that we can claim that it is 100 percent safe. The byproduct of nuclear power or it’s waste is weapons grade plutonium. That is enough to make me question the sanity of utilizing this option. There has never been a permanent solution for the question of waste storage.

There would certainly be a decrease of carbon dioxide emissions if we pursue this course, however is that enough? We have the technology for several different course to pursue. The carbon dioxide emission problem would simply cease to exist with renewable energy resources generating our electricity. The money needed for this option is not available, but if we can spend so recklessly on nuclear power, could we not use the same funds for sustainable and renewable energy sources?

I am saddened to say that in some cases utility operators, owners of the aging nuclear plant system would not invest in installing new power transmission lines to enable more wind turbine or solar power systems. Too costly, and not part of the scope of their work. This from the people selling us our electric power. My bills have increased over the past year by 20 percent. My income certainly did not increase by anywhere near that amount.

We should at least look at this problem and lobby our elected officials to make a stand for the sake of all Americans, for the sake of the people of earth in general. The utility companies work for you and me, write to them, we are their customers. We should at least try.

Why don’t we investigate wind power or solar power, there would be costs, but that is another article altogether. Just bear in mind that nuclear power is not renewable or sustainable.