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With the Green Party Holding the Balance of Power, British Columbia is Capable of Facilitating an Energy Miracle

Bill Gates has called for an energy miracle and that is precisely what the new political alignment in British Columbia can produce.

The Oxford dictionary defines a miracle as an exceptional product or achievement, or an outstanding example of something therefore the use, reduction, reuse and recycling of the heat of global warming to useful work can rightfully be described an energy miracle.

The following schematic shows the widely accepted view of greenhouse gases being trapped in the atmosphere by incoming solar radiation.

Human activities have added huge quantities of carbon dioxide and other greenhouse gases to the atmosphere and the oceans with well documented and escalating consequences. Ninety percent of this heat is being stored in the oceans and in accordance with the second law of thermodynamics, heat accumulated in the tropics will move to the poles where it melts the icecaps leading to sea level rise.

About twenty percent of the carbon dioxide released to the atmosphere annually is still going to be there a thousand years from now, and beyond, because this accumulation is irreversible under normal circumstances.

Per the following graphic, besides the poles, the deep ocean is an alternative heat sink into which warming heat can be relocated and during this rearrangement productive work can be derived and the abyss can become an alternative repository for atmospheric carbon that uses an electrochemical process that produces hydrogen and the antacid magnesium bicarbonate.

Warm water floating over cold is a stable configuration. Surface heat however can be used to boil a low-boiling-fluid to produce a vapor that travels at about a quarter of the speed of sound to a depth of 1000 meters where ocean water approaches its maximum density at a temperature of 4o C. In transit this vapor can drive a turbine to produce work and then be condensed by the cold water to release the working fluid’s latent heat of condensation. From the depths, the relocated heat takes about 250 years to return to the surface through diffusion at a rate of about 4 meters/yr and once back on the surface the heat can be recycled through heat engines with the result, in about 3,250 years, approximately 13 energy cycles, all the heat of global warming can be reduced, reused and recycled into useful work.

It has been estimated that since 1993 the oceans have retained an additional 335 terawatts (TW) of heat annually and this accumulation is accelerating. The conversion of this heat to work could currently produce 1.7 as much energy as is currently being derived from fossil fuels and could continue to do this, miraculously, for the next three millennia at a minimum.

By isolating warming heat within the tropics, it can not melt the icecaps which are already contributing about 80% of current sea level rise. The coefficient of expansion of sea water is also twice as high on the ocean’s surface, in the tropics, as it is at 1000 meters therefore sea level rise is reduced by moving surface heat into these depths.

The principal behind ocean thermal energy conversion, OTEC, has been around for 130 years but the current technology does not address the environmental question posed by the distribution of 146,800 kg/s of 4o C water to near the surface with each 50MW of energy produced. Heat displaced at the surface must go elsewhere, including towards the poles where it is available to melt the icecaps or at a minimum out of the prime OTEC producing areas where it is anergy (diluted or disorganized energy, which cannot be transformed into work).

This massive distribution of water requires large and costly infrastructure and degrades the energy potential of the OTEC resource by about 75%.

By using a low-boiling-point fluid to transfer heat through evaporation and condensation, much larger quantities of heat can be moved per kilogram of fluid than can be transferred by moving the same mass of seawater thus the size and cost of the piping of systems of the deep-water condenser design are reduced, while the thermodynamic efficiency is significantly increased and the heat is contained within the tropics.

An ammonia working fluid moves 2,750 kg/s compared to 146,800 kg/s of water for a conventional 50 MW OTEC plant. Typically, OTEC operates between temperatures of about 28o C and 4o C and about 25% of this heat is lost both to the evaporator and the condenser, which are both at the surface therefore the theoretical Carnot efficiency is about 1-(283/295) or about 4%.

With BC technology the exhaust from the turbine is condensed by cold water at a depth of 1000 meters therefore more of the cold resource can be used in the condenser and the rise in the temperature across the heat exchanger can be reduced to about 2o C. Likewise since the surface water is contiguous to the evaporator more of it can be used and the temperature drop across the evaporator can be reduced to about 2o C. Furthermore, vapor exiting the evaporator rises in temperature due to gravity operating on a 1000-meter-long column of gas. In the case of an ammonia working fluid, the temperature increase of a gas column 1000 meters long is about 5o C therefore the Carnot efficiency is 1-((277-2)/(301-2+5)) or about 9.5%.

Using a program otec.exe, the late Melvin Prueitt, physicist with the Los Alamos National Laboratory, calculated a system of this design produces a gross 59.4MW of power, requiring 4.66MW of pumping for a net of 54.7MW and a net efficiency of 7.6%.

The thermodynamic principles of OTEC are well established. Three industrial consortiums are currently competing for OTEC markets including the French group DCNS who in 2014 with its partner Akuo Energy was selected as part of the European NER 300 programme to develop a pilot, offshore, 10MW, plant on the Caribbean island of Martinique, due to be operational in 2020. Lockheed Martin has a small land-based OTEC prototype and is working on a project in Hawaii and Japan and Korea are partnering to address the OTEC market.

These all use a large cold water pipe design that limits the resource and does not maximize the environmental benefit.

Solar ocean energy systems (SOES) can provide four times as much as power as the conventional approach and could facilitate the hydrogen economy.  To get the power generated by these plants to shore, the electricity can be converted to hydrogen that concurrently precipitates carbonates and bicarbonates into the oceans and neutralizes the increasing acidity of the oceans. For every tonne of hydrogen produced, avoiding 11 tonnes of CO2 emissions, approximately 38 tonnes of CO2 are consumed and stored in the depths.

Currently energy is a $6 trillion/yr market segment that needs to double by 2050.

SOES proposes to service this market with a 20% surcharge over the current cost of energy for the reduction in surface ocean heat load, reduced thermal ocean expansion and sea-level rise, storm surge mitigation, ocean acidity mitigation and water production.

This is only 20% of the current environmental cost of business estimated in 2013 at $4.7 trillion/yr by the Economics of Ecosystems and Biodiversity program backed by the Group of Eight economic powers and the United Nations Environment Program.

Canadian patent application, 2,958,456, method and apparatus for load balancing trapped solar energy was filed, February 21, 2017.

The following table demonstrates how the climate and energy problem can be profitable address over the next 30 years.

The assumptions associated with the table are as follows:

  1. The 10 MW plant is land-base.
  2. All other plants are of the floating ship design.
  3. The cost of the 100MW SOES plant is 66 percent of the base cost of the conventional 100 MW plant.
  4. Each doubling of the size of a 100MW plant lowers plant cost by 22%.
  5. Cost of ship designs by N. Srinivasan and M. Sridhar, “Study on the Cost Effective Ocean Thermal Energy Conversion Power Plant,” Offshore Technology, pp. 1-13, 2010.
  6. All cost assumptions from MIT thesis, Assessment of Ocean Thermal Energy Conversion by Shylesh Muralidharan, B. Tech. Mechanical Engineering, Pondicherry University.
  7. Revenue from plants is 1.38 times current revenue from primary energy.
  8. The environmental benefit is 20% of the current environmental cost of business estimated in 2013 at $4.7 trillion/yr.

Contrary to the protestations of Alberta’s Premier Notley, these are the jobs and economic opportunities the province of British Columbia needs and its citizens desire.

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