jedcstuff

2006-03-20

Energy sources: energy in vs energy out

Thinking about energy sources, and the sum of all the specific energies that it takes to provide them in an ongoing way, appears to me to be one of the more important endeavors needed in the present day time frame. Yet, there does not seem to usually be an accurate evaluation of all the energy that goes into the devices that produce the energy we use. It is not just the dollar cost of fuel as it goes into the powerplant; this might not be obvious yet.

Abundant economical ever available energy is one of the key ingredients for our level of civilization. Fossil fuels has been the resource that has enabled the building of industrialized civilization. And it is necessary to keep energy available to keep civilization going at our level or better. It is an important issue, yet as the difficulty of providing energy increases rapidly, evaluation of all the factors need re-examination.

For example, a decade or so ago someone made an evaluation of solar cells energy deliverance ability, vs cost of manufacture ... the energy cost of manufacture, that is. This way of thinking seems essential for effective thinking about ways to provide the energy needed now and in future. That report found that it took more energy overall to manufacture the solar cells, than the solar cells would be able to supply in their useful lifetime. The report went on to point out that the places using the solar cells was what made them valuable, since they could be used to power remote devices and facilities by sun power, without having to run powerlines to the distant site, nor endure the cost of transportation and maintenance recharging of batteries to power the remote instruments. Many of the safety telephones along freeways economically use solar cells for this reason, that they do not need power lines run to power the phones.

For the major amount of electrical power used by our country, however, power will go around on existing power lines.

The question becomes how much energy does it cost to conceptualize, design, build, deliver, install, maintain and ensure continual energy input to the energy supplier.

Wind power requires the wind turbines creation, and rent to pay landowner where the windpower generator is located, maintenance of the windmill, and eventual energy cost of recycling or disposal of the worn out machine downstream.

What is the total energy cost that goes into the machine, such as the cost of commute of the employees that build and assemble all the parts, and the energy required to smelt, cast, machine and process its component materials? In this case, it is not likely there will be a cost of ensuring availability of wind to actually input energy to the windmill, but some other kinds of energy sources do have, such as the cost of fossil fuel (including coal) powered generators, and fuel for nuclear reactor powerplants, is a very significant factor, as well as cost of subduing the toxic byproducts produced during such energy provision.

The potentials of Satellite Solar Power Stations in GEO or the Moon, without significantly contributing to greenhouse effect global warming, are not presently economical enough to build despite their attractiveness for abundant electric power delivered worldwide, because of the immense cost (especially including energy costs) of using rocket propulsion to deliver the construction materials up there, along with all it takes to build and maintain that huge equipment up there. If transportation techniques are created that enable them to be delivered up into high earth orbit economicaly, however, creation of those solar electric power stations in space, where there is abundant sun power available 24 hours a day, rain or shine below, could make them highly attractive as power sources. A big "if", however; they have to be made physical reality, to be there to be used in time of need. Meantime, we need to optimally deal with what we have already got.

It is the overall energy it takes to provide an energy source, as compared to the overall energy the energy source delivers to the user, that is the key parameter. Now, how do we implement means for determining the total sum of all the specific energies it takes to ongoingly provide a particular energy source to the user?

Jim Cline 20060320

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