Sustainable Energy Technologies MSE0290 Miscellaneous

Contents Cogeneration Fuel cells Geothermal

Cogeneration

Cogeneration POWER ONLY ELECTRICITY POWER PLANT FUEL MECHANICAL ENERGY USEFUL POWER FUEL MECHANICAL ENERGY WASTE HEAT WASTE ENERGY STEAM CYCLE COOLERS – HEAT IS WASTED ENGINE OR TURBINE

Cogeneration COGENERATION ELECTRICITY POWER PLANT FUEL USEFUL POWER FUEL MECHANICAL ENERGY HEAT USEFULL HEAT STEAM CYCLE ENGINE OR TURBINE

Cogeneration COGENERATION POWER PLANT ELECTRICITY USEFUL POWER FUEL MECHANICAL ENERGY HEAT USEFULL HEAT COGENERATION: power, and/or heat (example:district heating), and/or mechanical energy, and/or steam and/or cooling Source: http://site.ge-energy.com/prod_serv/products/recip_engines/du/cogen_systems/refrigeration.htm

Cogeneration COGENERATION IS SUISTANABLE WAY OF ENERGY PRODUCTION GENERAL SUMMARY COGENERATION IS POSSIBLE WHEN CONSUMERS ARE AVAILABLE AND SUPPLY OF PRODUCED ENERGY IS FEASIBLE (COMPETETIVE) PRICE. COGENERATION IS SUISTANABLE WAY OF ENERGY PRODUCTION … significant economic, energy and environmental benefits would result from increased policy commitment to CHP. https://www.iea.org/publications/freepublications/publication/CHPbrochure09.pdf

FUEL CELLS

CORE ELEMENT – HYDROGEN FUEL CELLS HYDROGEN PRODUCTION CORE ELEMENT – HYDROGEN Some feedstock and process alternatives Source: https://www.iea.org/publications/freepublications/publication/hydrogen.pdf

FUEL CELLS HYDROGEN PRODUCTION Source: https://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/h2_tech_roadmap.pdf

FUEL CELLS the carbon dioxide release HYDROGEN PRODUCTION – Steam reforming Steam and hydrocarbon enter the reactor as feedstock, and hydrogen and carbon dioxide are generated at the end of the process. The process is governed by the reactions High temperature (catalyst nickel) Low temperature (catalyst copper or iron) the carbon dioxide release Source: http://large.stanford.edu/courses/2010/ph240/chen1/

FUEL CELLS HYDROGEN PRODUCTION - Electrolysis More types: ALKALINE ELECTROLYZERS, SOLID OXIDE ELECTROLYZERS Read more: http://energy.gov/eere/fuelcells/hydrogen-production-electrolysis

FUEL CELLS HYDROGEN PRODUCTION - Solar Conversion Researchers in Germany have made a breakthrough with the development of a cost-effective and efficient solar fuel device that can store nearly 5% of solar energy in the form of hydrogen. Read more: http://www.pv-magazine.com/news/details/beitrag/efficient-solar-fuel-device-with-simpler-cell-design_100012211/#ixzz3zf0eNnmy 31. JULY 2013

FUEL CELLS - Materials for anode and cathode FC MAIN TYPES MAIN DIFFERENCES - Materials for anode and cathode - Electrolyte (solid, liquid, toxic, etc) - Operating temperatuure COSTS APPLICATIONS READ MORE: http://www.fuelcelltoday.com/technologies/sofc http://www.bloomenergy.com/fuel-cell/solid-oxide-fuel-cell-animation/

FUEL CELLS R&D. Example Fachhochschule Stralsund Source: http://www.fh-stralsund.de/ps/tools/download.php?file=/internet/dms/psfile/docfile/40/Research_a53d8b3d003eb2.pdf&name=Research_and_Education_in_the_field_of_Renewable_Energies_2.pdf&disposition=inline

FUEL CELLS GRID OPERATION R&D. Example Fachhochschule Stralsund Source: http://www.fh-stralsund.de/ps/tools/download.php?file=/internet/dms/psfile/docfile/40/Research_a53d8b3d003eb2.pdf&name=Research_and_Education_in_the_field_of_Renewable_Energies_2.pdf&disposition=inline TRANSPORT

? FUEL CELLS Hydrogen vehicles Source: http://www.toyota-global.com/innovation/environmental_technology/fuelcell_vehicle/ ?

SUSTANABLE HYDROGEN IN GENERAL: FUEL CELLS Sustainable electricity or biomass to produce HYDROGEN means SUSTANABLE HYDROGEN

FUEL CELLS Availability Source: http://h2me.eu/about/hydrogen-refuelling-infrastructure/

Geothermal

GEOTHERMAL POTENTIAL – TEMPERATURE GRADIENT Potential

GEOTHERMAL Global electricity generation in 2013 was 23 322 TWh STATISTICS Geothermal typically provides base-load generation, since it is generally immune from weather effects and does not show seasonal variation. Capacity factors of new geothermal power plants can reach up to 95%. The base-load characteristic of geothermal power distinguishes it from several other renewable technologies that produce variable power. In 2012, global geothermal power capacity was 11.4 GW and generated around 72 TWh of electricity. Geothermal electricity provides a significant share of total electricity demand in Iceland (25%), El Salvador (22%), Kenya and the Philippines (17% each), and Costa Rica (13%). Global electricity generation in 2013 was 23 322 TWh

GEOTHERMAL TECHNOLOGIES Electricity production 1. Dry steam plants 2. Flash steam plants 3. Binary plants Enhanced or engineered geothermal systems (EGS)

GEOTHERMAL TECHNOLOGIES Electricity production 1. Dry steam plants, which make up about a quarter of geothermal capacity today, directly utilise dry steam that is piped from production wells to the plant and then to the turbine. Control of steam flow to meet electricity demand fluctuations is easier than in flash steam plants, where continuous up-flow in the wells is required to avoid gravity collapse of the liquid phase

GEOTHERMAL TECHNOLOGIES Electricity production 2. Flash steam plants, which make up about two-thirds of geothermal installed capacity today, are used where water-dominated reservoirs have temperatures above 180°C. In these high-temperature reservoirs, the liquid water component boils, or “flashes,” as pressure drops.

GEOTHERMAL TECHNOLOGIES Electricity production ….. separated steam is piped to a turbine to generate electricity and the remaining hot water may be flashed again twice (double flash plant) or three times (triple flash) at progressively lower pressures and temperatures, to obtain more steam. Chemistry Challenges in Geothermal Power Generation. I . Richardson, S. Addison, R. Lawson 2014.

GEOTHERMAL TECHNOLOGIES Electricity production Binary plants constitute the fastest-growing group of geothermal plants, because they are able to also use the low- to medium-temperature resources, which are more prevalent. Binary plants, using an organic Rankine cycle (ORC) or a Kalina cycle, typically operate with temperatures varying from as low as 73°C (at Chena Hot Springs, Alaska) to 180°C. In these plants, heat is recovered from the geothermal fluid using heat exchangers to vaporise an organic fluid with a low boiling point (e.g. butane or pentane in the ORC cycle and an ammonia-water mixture in the Kalina cycle), and drive a turbine. Today, binary plants have an 11% share of the installed global generating capacity and a 44% share in terms of the number of plants.

GEOTHERMAL TECHNOLOGIES Electricity production Binary plants. Binary plants, using an organic Rankine cycle (ORC) or a Kalina cycle. typically operate with temperatures varying from as low as 73°C (at Chena Hot Springs, Alaska) to 180°C.

GEOTHERMAL The process of a organic Rankine using R11 as the working fluid TECHNOLOGIES Electricity production Working fluids. Examples. HCFC123 (CHCl2CF3), PF5050 (CF3(CF2)3CF3), HFC-245fa (CH3CH2CHF2), HFC-245ca (CF3CHFCH2F), isobutene ((CH3)2C=CH2), n-pentane and aromatic hydrocarbons http://www.eng.usf.edu/~hchen4/Organic%20Rankine%20Cycle.htm

GEOTHERMAL Kalina cycle TECHNOLOGIES Electricity production It uses a solution of 2 fluids with different boiling points for its working fluid.  Mainly: ammonia-water as working fluid For Advanced Kalina Cycle ohter mixtures http://www.eng.usf.edu/~hchen4/Organic%20Rankine%20Cycle.htm

GEOTHERMAL ORC versus Kalina cycle TECHNOLOGIES Electricity production http://www.aidic.it/cet/13/35/037.pdf

GEOTHERMAL TECHNOLOGIES EGS Geothermal technologies using hot rock resources could potentially enable geothermal energy to make a much larger contribution to world energy supply. Technologies that utilize hot rock resources are also known as enhanced or engineered geothermal systems (EGS). These systems aim at using the earth’s heat where no or insufficient steam/hot water is available or where permeability is low. EGS plants differ from conventional plants only as far as heat/steam extraction is concerned. EGS technology, therefore, is centred on engineering and creating large heat exchange areas in hot rock. The process involves enhancing permeability by opening pre-existing fractures and/or creating new fractures.

GEOTHERMAL TECHNOLOGIES Heat production Geothermal energy can also provide heat. Even geothermal resources at temperatures of 20°C to 30°C (e.g. flood water in abandoned mines) may be useful to meet space heating demand or other low-temperature applications. Geothermal “heat-only” plants can feed a district heating system, as can the hot water remaining from electricity generation, which can also be used in applications demanding successively lower temperatures. Because transport of heat has limitations, geothermal heat can only be used where a demand exists in the vicinity of the resource

GEOTHERMAL GENERAL SUMMARY Conventional geothermal is a mature technology that can provide baseload power or year-round supply of heat. The resource can be exploited only in favourable regions (a constraint that can be relaxed when EGS systems are ready to be commercialised). Matching heat demand to resource availability can be difficult given the costs and difficulty of transporting heat long distances.