Renewable Electrolysis (RE)

Systemic supply side inefficiencies exist when there is no way to store electricity generated in times of off peak or lower seasonal demand. These "losses" could be recovered by adopting Renewable Electrolysis (RE). Significant under-utilized generating capacity is revealed by comparing actual annual kWh(e) output achieved compared with "Summer rate capability".

In RE, electrical energy is captured and stored as compressed hydrogen gas released by electrolysis, which can be re–converted into electricity using fuel cells to meet up-turns in demand as base load. When complemented progressively by new renewable energy sources – wind or solar photo voltaic arrays – RE would enable GHG intensive plants to be phased out. Also modular RE units could be sited near substations serving population centers. Decentralizing capacity in this way would make it more difficult to disrupt supplies by cyber attacks and create many more manufacturing, installation and maintenance jobs in the process. Recent reports of hacks into the US power grid are thought by some to be preparatory to larger disruptions.

Renewable Electrolysis.

The Foundation is indebted for the co-operation of the DOE - NREL and particularly to Darlene Steward et. al. and NREL/PR-560-47547 from proceedings of the HTAC meeting February 11, 2010. (Note that 1kg H2 is equivalent energy to 1gal gasoline. The Florida location is not suited to the competitive Pumped Hydro or Compressed Air Energy Storage technologies.) To see the presentation given on February 11, 2010; click here: Renewable Electrolysis.

Note: Some of the manufacturers approached in regard to larger static fuel cells have their business models tuned to using natural gas as their energy source, which is perfectly reasonable in view of the availability of natural gas in the market place. Their process requires natural gas to be reformed into hydrogen and then the hydrogen is the energy source for the fuel cell, as opposed to electrolyzing separation of hydrogen from water. However, a manufacturer offers a 1 MW PEM hydrogen fuel cell at a cost of about $4million.

A very good source on Hydrogen technologies is Technical Report NREL/TP-560-46267, September 2009 by Darlene Steward et al - Click here to read Darlene . Essentially, hydrogen energy electrolysis and storage offers an opportunity to harness supply side generation capacity which is not used in the absence of storage. Efficiencies suffer where plants are forced to ramp down to accommodate both seasonal and daily cyclical reduced demands. When this is complemented by progressive expansion of clean energy generation by wind or solar PV arrays transition from GHG intensive fossil fuels to clean technologies can be made.

For example, based upon 2008 data, the scope for supply side increases in efficiencies from the four coal fired plants of the Crystal River Energy Complex (CREC) has a potential for 29.56% or 683 MW(e) equivalent, rising to more than 800 MW(e) including the current nuclear facility. Today's achievable Round Trip energy efficiencies (H2 hydrolysis thro' fuel cell) are estimated to be between 40% and 47%. Another significant issue is the ability to site PV arrays with Renewable Electrolysis close to a substation near to a conurbation center, say Orlando or The Villages already connected to the CREC.

RE would facilitate higher supply side efficiencies, at significantly lower costs, in an infinitely environmentally preferable manner, and be beneficial instead of harmful to human health than, say, adding nuclear generating capacity. A smoother transition strategy to an altogether cleaner nation-wide could result and create jobs so urgently needed both in manufacture and installation and maintenance.

See also News Items on this website dated 23 September, 23 October and 27 October, 2010.

A Renewable Electrolysis Scenario.

An alternative "Renewable Electrolysis" scenario is described avoiding much of the negative environmental consequences which does not appear to have been addressed in the draft NUREG-1942 DEIS. Time and wealth consumed with PEF LNP proposition could be applied to bring on stream increased power capacity in a radically shorter time scale, for significantly less cost, creating local employment opportunities so urgently needed and avoiding degradation of highly valued natural resources. Earlier elimination of GHG and methyl mercury emissions from earlier closure and decommissioning of the dirty coal-fired units at the CREC would be a landmark achievement for PEF.

For example, the hydrogen plant postulated below could be accommodated in some seven cubic meters of space.

PV arrays could be brought on stream as described below (as similar installations have already been provided elsewhere in Florida), together with hydrogen plant providing for base load supply, both of which could be progressively expanded over time, taking advantage of cost reductions as technologies mature :

• solar energy PV arrays and inverters could be installed on the LNP site to serve prescient increases in demand,
• hydrogen electrolysis and storage plant could create an off-grid local energy reserve. The energy resource for the hydrogen plant could be derived from off-peak grid supplies in times of lower demand enabling more efficient operating schedules of existing plants, complemented by yield from solar energy arrays both on site and on adjacent land.
• future disabling events to the CREC nuclear facility could be recovered more expediently using the reserve,
• a simple energy arbitrage scenario is postulated for the hydrogen plant consisting of an initial 300 MWh nominal storage capacity that is charged during off-peak hours (18 hours per day on weekdays and all day on weekends) and discharged at a rate of 50 MWh for 6 peak hours on weekdays. Process water would be electrolyzed to produce hydrogen, for storage as compressed hydrogen gas in above ground steel tanks for use in polymer electrolyte membrane (PEM) fuel cells. Some estimated time and cost parameters are suggested (excluding any benefit from possible federal subsidies):
  1. acquire land bank for expansion of PV system, say, 5,000 acres @ c. $100million, bringing total acreage to 10,000 acres [say, 1 year],
  2. PV indirect costs (engineer, procure,construct) @ $11million [over say, 2.5 years],
  3. build initial 10MW (AC) PV array on 60 acres @ $40million direct cost (incl. inverters c. $4million),
  4. initial PV total cost $151million - excluding land prepn. [elapsed time, say, 3 years],
  5. Hydrogen plant (Electrolyzer, Hydrogen storage, Fuel cells) consisting of, 50 electrolyzer units to yield 52,300 kg/day H2 (run in of-peak hours only) Process water Cooling system Transformer, Thyristor, Electrolyzer Unit, Lye Tank, Feed Water Demineralizer, Hydrogen Scrubber, Gas Holder, 2 Compressor Units to 30 bar (435 psi), Deoxidizer, Twin Tower Dryer.
  6. Estimated net present (2011) cost of H2 plant @ $225million.

Note: Using hydrogen for energy storage provides unique opportunities for later integration between the transportation and power sectors. Producing a small amount of excess hydrogen (five 280-kg tanker-truck loads or 1,400 kg per day) reduces the overall levelized cost of energy for this scenario by about 6% compared with the purely energy arbitrage scenario.

Fuel Cells. A fuel cell is an electrochemical device that combines hydrogen and oxygen to produce electricity, with water and heat as its by–product. As long as fuel is supplied, the fuel cell will continue to generate power. Since the conversion of the fuel to energy takes place via an electrochemical process without combustion (electrolysis), the process is clean, quiet and efficient – two to three times more efficient than fossil fuel burning. Click to view the Energy Justice.net fact sheet on Hydrogen and fuel cells.

No other energy generation technology offers the combination of benefits that fuel cells do. In addition to low or zero emissions and fuel portability, benefits include high efficiency and reliability, multi–fuel capability, citing flexibility, durability, salability and ease of maintenance. Fuel cells operate silently, so they reduce noise pollution as well as air pollution and the waste heat from a fuel cell can be used to provide hot water or space heating for a home or business.

There are many uses for fuel cells – right now, all of the major automakers are working to commercialize a fuel cell car. Fuel cells are powering buses, boats, trains, planes, scooters, forklifts, even bicycles. There are fuel cell–powered vending machines, vacuum cleaners and highway road signs. Miniature fuel cells for cellular phones, laptop computers and portable electronics are on their way to market. Hospitals, credit card centers, police stations, and banks are all using fuel cells to provide power to their facilities. Wastewater treatment plants and landfills are using fuel cells to convert the methane gas they produce into electricity. Telecommunications companies are installing fuel cells at cell phone, radio and 911 towers. The possibilities are apparently endless with hydrogen in abundant supply and process technologies becoming more efficient as time passes.

Hydrogen is potentially the most abundant and inexhaustible energy source available. However it cannot be harvested or mined or pumped from the ground. To isolate it as the energy carrier that it is, one has to break the bonds to other elements to which it is attached in nature. Unlike electricity which does not "keep", hydrogen can be stored or moved from place to place for use for work as a compressed gas, or as a super chilled liquid or in suspension with metal hydrides. Remember that hydrogen is the basis of all the so–called hydrocarbon fuels we depend upon today. Hydrogen burns easily. Isolating hydrogen requires the application of energy to sever the bonds. The inherent value of hydrogen as fuel lies in extending the lifetime and versatility of electricity.