GE1308 - Energy: Today and Tomorrow

Dr. Sam Hsien-Yi HSUSchool of Energy and Environment

City University of Hong Kong

sam.hyhsu@cityu.edu.hk

1School of Energy and Environment, City University of Hong Kong

LECTURE TOPIC1 (a) Introduction; (b) Organization and motivation2 Basic energy sciences3 Fossil fuels power plant4 Power plants environmental impacts and controls5 Nuclear energy and risk assessment6 (a) Demand side management and energy efficiency; (b) Quiz

7 Guest Speakers8 Renewable energy (I): Wind and water9 Renewable energy (II): Geothermal and solar10 Renewable energy (III): Bioenergy11 (a) The hydrogen economy; (b) Quiz

12 Group presentation13 Laboratory course14 Field trip

2School of Energy and Environment, City University of Hong Kong

3School of Energy and Environment, City University of Hong Kong

Time scale: ~ million years

Source: http://www.eia.gov/energyexplained/index.cfm?page=oil_home

4School of Energy and Environment, City University of Hong Kong

5School of Energy and Environment, City University of Hong KongSource: National Energy Technology Laboratory (NETL), DOE, USA

6School of Energy and Environment, City University of Hong Kong

Source: http://blogs.nature.com/news/2011/05/understanding_the_complete_mel.html

7School of Energy and Environment, City University of Hong Kong

While HK consumes less energy in the transportation sector, as a metropolitan city, HK has a higher number of buildings

Source: http://www.eurolutions.com/contact.html

8School of Energy and Environment, City University of Hong Kong

Clustering of many wind turbinesin a regular array in a region ofgood winds

Turbines are typically spaced 5-9rotor diameters apart in the along-wind direction, and 3-5 rotordiameters apart in the cross-winddirection To minimize aerodynamic

interference 5% reduction in power output

compared to an isolated turbine Clustering reduces costs

(economies of scale for installation), and takes better advantage of the best wind sites

Source: In volume 2 – Carbon-free energy supply (by L.D. Danny Harvey)

9School of Energy and Environment, City University of Hong Kong

Ludington Pumped Storage Plant , USA

Peak load demand occurs during the day-time, and the night-time load issmaller

Use the night-time spare generation capacity to pump water up from turbinelevel to high storage reservoirs

Stored water is available for driving water turbines during peak demand This maximizes utilization of the plant

Source: http://www.consumersenergy.com/content.aspx?id=1830

10School of Energy and Environment, City University of Hong Kong

One of just three tidal power plants in the world, a 20 MW facility

In-stream tidal turbine

Barrage across a river

Source: http://www.nspower.ca/en/home/environment/renewableenergy/tidal/photos.aspx

11School of Energy and Environment, City University of Hong Kong

Source: In volume 2 – Carbon-free energy supply (by L.D. Danny Harvey)

12School of Energy and Environment, City University of Hong Kong

Radiation

Photovoltaic (direct conversion

to electricity)Solar thermal

Heating of air Heating of water Thermal concentration

Thermodynamic cycles

13School of Energy and Environment, City University of Hong KongSource: In volume 2 – Carbon-free energy supply (by L.D. Danny Harvey)

14School of Energy and Environment, City University of Hong Kong

Used both as shadingand as electricitygeneration

Source: In volume 2 – Carbon-free energy supply (by L.D. Danny Harvey)

15School of Energy and Environment, City University of Hong Kong

Wind Hydro Tidal & wave

Geothermal Solar thermal Photovoltaic

Among the different renewable options, energy from biomass is more suited to be adopted as liquid transportation fuels. The rest better for electricity generation (unless electric or hydrogen vehicles are widely available).

Biomass

16School of Energy and Environment, City University of Hong KongSource: http://goldengrainenergy.com/ethanol_process.htm

17School of Energy and Environment, City University of Hong Kong

Produce hydrogen from electricity (which is generated from renewable sources)

Hydrogen can be stored and transmitted or transported long distance Either convert back to electricity (via fuel cells) or used directly

Source: http://re.emsd.gov.hk/english/gen/gother/gother_hyd.html