The Problem
The energy requirement of earth’s people is large and growing ever larger as population and demand per person increases. In the past, it was easily satisfied by hydroelectric, nuclear and fossil fuels (oil, natural gas, and coal). But hydro sites are used up. Nuclear power has certain safety problems and how to deal with the spent fuel has not yet been determined. Oil (also a serious polluter) is nearing its production peak, and it will be followed by gas in a relatively short time. Coal will take much longer (approximately 200 years) to reach its peak, but it is a much more polluting fuel. Indeed all of the fossil fuels are polluting, in that they generate acids and carbon dioxide, but coal is the worst. The acids cause acid rain that kills plants and fish. The carbon dioxide is believed by most to cause climate warming with a resultant reduction in glaciers and ice caps, an increase in sea level, and a shift in desert zones toward the poles along with a resultant loss of agricultural land (see Aquater2050 Paper No. 1). Thus we have a problem. How do we provide for the earth’s growing energy needs with fuel dwindling and pollution and carbon dioxide production increasing?
Is Action Required?
Many have objected to the premise that oil and especially natural gas are nearing their production peak. Some have objected to the idea that carbon dioxide production causes climate warming. Thus it has been proposed that no action be taken until the oil shortage and climate warming have been unequivocally proved. The difficulty with this “wait and see” procedure is that it takes a long time for a new energy source to ramp up and replace the old one that is in need of replacement. Thus a crisis of major proportion with the shortages and high prices that disrupt the economy could result. Also, damage due to a warmer climate may become catastrophic if we wait too long. There should be a new energy source in the development pipeline capable of taking over for a failed source.
The Solution
Thus we need to look for an energy source that has the following characteristics.
It must be:
O Plentiful enough to cover the world’s needs in the long run.
O Free from pollutants and carbon dioxide production.
O Price competitive (<$0.08/KWH) with existing sources, so it can start replacing them now and later become a major energy supplier.
O Able eventually to provide fuels for portable power plants (autos, aircraft, etc.).
O Able to use the earth’s existing energy distribution systems now.
A desirable characteristic is that it should be:
O Able to be developed and move into the marketplace without government assistance, or bank loans. The development cycle will be too slow and complex to meet the near-term energy and air pollution reduction needs if the government is involved.
Several good options have been proposed.
O Land based solar cells and/or solar thermal plants
O Land based wind turbines
O Shore based wave generators
O Nuclear fusion
O Nuclear fission
O Land based deep thermal wells
O Fuels such as alcohol and oil obtained from food crops, waste wood, kelp and algae.
O Ocean based wind turbines, wave generators and solar cells
Let us investigate them one at a time and match them against the requirements.
Land based Solar cells and solar thermal systems are non-polluting, but for base load and portable operation, they have serious problems. They are very expensive (~$0.17/KWH when available), require expensive storage systems to operate when the sun is down or obscured (Load Factor~0.4 to 0.6 in desert zones, less elsewhere-note load factor is the fraction of time the system is available for use) and need huge tracts of carefully selected land for each KW of power generated. (~0.005 KW/sq ft). Thus land-based solar cells and solar thermal are not suited for general base load generation that must be economically competitive and reliable. Solar cells appear best suited for specialty use where cost and area is less important, such as on top of electric cars to extend their battery range, or on top of houses to cover the day-time peak load. Solar thermal appears best suited for use in special areas where the climate conditions and load characteristics work together to make these generators more competitive.
Land based wind turbines are also non-polluting and expensive, but they are not as expensive as solar cells (~$0.10/KWH when available). However, they require carefully selected windy sites that are not common, and they are not always available (Load Factor~0.5 to 0.7 in good sites, less elsewhere). Thus, these generators are not suited for base and portable load generation that must be cost competitive and reliable. They appear best suited for operation in high energy cost areas on an as available basis.
Shore based wave generators are also non polluting but expensive, however not as expensive as land based wind turbines (~$0.09/KWH when available). They require carefully selected wave sites that are not common, and they are not always available (Load Factor~0.4 to 0.6 in good sites, less elsewhere). Again, these generators are not suited for base load generation that must be competitive and reliable. They appear best suited for operation in high energy cost areas on an as available basis.
Nuclear fusion is not currently practical, and is not expected to be practical in the foreseeable future.
Nuclear fission reactors are currently being used for base load (Load Factor ~1) and can operate at ~$0.08/KWH). There is enough fuel to last more than 100 years without using breeder reactors (reactors that generate more fuel from U238 than they use. Actual fuel is from U235 and Pu). If we use breeders, there is enough fuel for several thousand years. Also, nuclear reactors are non-polluting-i.e. they do not emit acids and carbon dioxide. Clearly this is a major competitor for base load operation. The problem with nuclear reactors is safety. The public is afraid of an accident that will cause radiation to escape. Further, spent fuel rods and other reactor parts are radioactive for a very long time (tens to hundreds of thousands of years). Safety procedures, fail-safe reactors and methods of storing and/or making these radioactive components safe have been worked out, but the political system has not been able to agree on which procedures to use in dealing with this problem, so older, less safe designs are still in use. The vulnerable element in the light water reactors currently being used in Japan and elsewhere is the coolant pump. Backup coolant pumps are always provided, but if all electricity is lost, both inside and outside the facility (as happened in Japan), the backup pumps are useless. The neutron absorbing control rods and emergency shut down systems will deploy without electricity and shut down the fission reaction, but the residual fission and radioactivity in the fuel rods will continue to heat the rods and eventually melt them down (as apparently happened in Japan). If the coolant pump is off line long enough (as also apparently happened in Japan), the rods may melt through the containment vessel and vent radioactive material to the environment. It appears feasible to design some reactors (for example-pebble bed reactors, certain fast reactors and some special micro reactors) with automatic energy production limits in the fuel elements so that the residual fission and radioactivity will not melt them down even if cooling is lost. Or, it may be possible to make acceptable modifications to the current light water reactor designs.
Deep thermal wells are non-polluting and may be competitive in cost. The expense is dependent on the cost of drilling a well down to the hot rocks deep within the earth’s crust. New chemical drilling techniques show promise, but cost estimates are not available. A pilot hole is now under way. If the pilot hole is inexpensive enough, these thermal wells can be used to provide base load. The fuel (earth heat near the surface) is available in many areas on the earth, and will last for the foreseeable future. It is non-polluting. It can use existing electrical distribution systems. The hole can even be used to sequester carbon dioxide. The only disadvantages of this generator are:
O It is unable to provide fuel for portable power plants (autos and aircraft), although this problem may become less important if electric cars take over the automobile market.
O It is not able to be developed and move into the marketplace without government assistance.
O It is not able to provide its own capital for initial production. Government aid may be necessary at first.
These disadvantages do not seem to be crippling, so this type of generator is definitely a candidate to replace coal, oil and gas.
Alcohol from corn is currently being produced and used with gasoline to power autos. This option cannot be thought of as a long-term solution, however. As population increases, the corn must be used for food. The same is true of oil from soybeans. This is not true of alcohol and oil from waste wood and sea crops such as kelp and algae. These sources provide no pressure on the food production capability; so long term production is possible and also desirable. It will help replace fossil fuels for portable applications in the long run. It should be noted, however, that it couldn’t replace fossil fuels for base load operations. Energy from plant growth is less efficient than that from solar cells, and it has already been noted that solar cells for base load are expensive. It requires far too much land (or sea) area to cover base load. It cannot even cover all of the fuel for portable power plants such as cars, trucks and aircraft. Thus energy from plants is best suited to supplying part of the fuel for portable power plants.
Ocean based wind turbines, wave generators and solar cells are non polluting and inexpensive. They can be operated on one platform or vessel to save capital expense. The cost per KWH is estimated at ~$0.03/KWH. Wind and wave turbines are the primary producers. Solar cells are expensive and consume so much area that they can provide only a tenth of the generated power, so they have only a backup roll. The vessel can be moved to find optimum operating conditions, so the Load Factor is ~0.85 to 0.95. The energy can be converted into fertilizer concentrate immediately with easy transport to land, and a ready market. This frees up natural gas for use to generate base load. It is also possible, with development, to convert the energy harvested on the ocean into gas or oil as fossil fuels peak out, so base load and portable applications can also be covered without using fossil fuels. The owner is also the operator, so overhead is saved. Part of the owner’s pay is the living quarters on the vessel. All of the critical and desirable characteristics are satisfied. The prototype is almost complete, and has been developed without government funds. Clearly this is a candidate to replace coal, oil and gas.
All of these candidates should be measured against fossil fuel generators. Current cost per KWH is ~$0.08/KWH wholesale in California. Oil production is nearing its peak (2015 to 2020), and the gas peak is expected to follow soon after. Coal production peak is not expected for ~200 years, but coal is the worst polluter. Indeed, fossil fuels are the worst polluters of all candidates (see Aquater2050 Paper No. 1), and coal is the worst fossil fuel. They are, however, well suited for both base load operation and portable applications (cars, trucks and aircraft).
Timing and Overall Capability
For timing, only the ocean based wind and wave vessels (called SEMAN) can start coming on line as oil peaks out. The reason this is possible is that Aquater2050 LLC is using a different development procedure and business model than is normal for an energy company. Development consists of building and testing one vessel (it is nearing completion). A SEMAN is capable of immediately making energy (and a profit), so people with the funds can individually build and operate their own SEMAN.
Production can be accomplished in any of the innumerable recreational boat builders available in most of the nations of the world. The skills required are those needed for construction using wood, fiberglass, glue and steel and aluminum fittings.
Aquater2050 LLC also has an Internet site (Aquater2050.com) operating. Part of the money received by this site will be put into a fund to supply building materials for those who don’t have money of their own to build a vessel. Banks would be reluctant to invest in SEMAN because the asset is portable and the technology new, and so the risk is difficult to assess. Thus the unemployed can also build and operate vessels. Since there can be more than one construction base operating, rapid production increase is possible.
As to overall capability, nuclear plants have the required capability, but the safety issue is slowing plant construction. Deep thermal wells have the required capability, but deep well drilling and other development issues will take a long time.
On the other hand, the oceans have the capability of supporting roughly 200 million SEMAN in high-energy areas (wind speed >15 knot). This number of SEMAN can cover the energy needed to replace fossil fuel generators as time goes on as well as sequester all of the carbon dioxide currently generated by fossil fuels. Thus Aquater2050 SEMAN can cover the fossil fuel replacement requirement and gradually draw down the carbon dioxide in the atmosphere at the same time.
Construction Capability
Since an enormous amount of construction is required to build 200 million SEMAN, it is proper to ask if the capability exists to do this construction and if the materials are available. SEMAN construction requires much the same skills as house construction and uses much the same materials (wood, fiberglass, glue, steel and aluminum fittings, carpet, and fabrics). In fact, the primary material used, birch plywood, comes from birch trees common in northern Russia, Finland and northeast US and it is a renewable material. The SEMAN is in fact a home for a family of four with some extra electrical additions (primarily sails and electric generators), so either a home or a SEMAN would have to be built for each new family as population increases. This situation contrasts with other green energy producers such as solar cells. Solar cells have a serious production limit caused by a shortage of both worker skills and refined solar cell materials, and could not ramp up into the dominant energy producer in a short time.
Thus no new skills or materials are required for SEMAN construction and building 200 million SEMAN is roughly the same as building 200 million homes that would have to be built anyway except for the electrical equipment. On a worldwide basis, 200 million homes over 40 years is not an impossible job.
Conclusions
Fossil fuels, the primary energy source for the planet, will continue to provide the majority of the world’s energy requirement in the near term, but they are nearing their production peak (excepting coal), and they are the primary polluters of the atmosphere. They must be phased out as rapidly as possible.
Nuclear fission appears to be the best immediate candidate to replace fossil fuels, for base but not portable loads; however effort must be expended to improve the safety problem.
Energy from growing plants (corn, soybeans, wood, kelp and algae) is too expensive and inefficient for use as base load. However, it appears well suited to help replace oil for portable power plants such as autos, trucks and aircraft, where the extra expense is less important. Complete replacement of oil using this energy source for portable power plants is not possible, however.
The best long-term candidates for the base load and portable energy applications are these:
O Ocean based wind and wave turbines and solar cells. (See Aquater2050.com for details)
O Deep thermal wells that capture heat to operate steam turbines.
These latter candidates appear capable of doing most of the job, and they have advantages. They will gradually fit into their market position without government intervention as they complete their development cycle, and thus replace fossil fuels in a natural way.
Land based solar, wind and wave generators appear best suited for specialty applications. They are in the process of filling that market now.
Note
1. More details and all references for this paper are given on Aquater2050.com
2. Unfamiliar terms (such as pebble bed reactor, etc) are defined on the Internet (Wikipedia)
3. To donate to help complete the prototype, click on “Add to Cart” button on the Home Page.
4. To see prototype progress, click on “SEMAN Prototype Update” on the Home Page.