Title: An Introduction to Gas Turbines
1An Introduction to Gas Turbines Microturbines
for DE ApplicationsWorld Energy Technologies
Summit10 11 February 2004
- Michael Brown Director
- World Alliance for Decentralized Energy (WADE)
- michael.brown_at_localpower.org
2What is Decentralized Energy (DE)?
- Electricity production at the point of use,
irrespective of size, fuel or technology
- High efficiency cogeneration / combined heat and
power (CHP) - Simultaneous production of useful power and heat
from single fuel source - The most efficient use of any fuel
- Based on gas turbines, microturbines, engines,
steam turbines, etc - On-site renewable energy
- On-grid and off-grid
3Origins of the Gas Turbine
- Concept envisualised at beginning of 20th Century
- First Industrial Gas Turbine built in 1931 by
Brown Boveri - In late 1930s focus shifted to aircraft
propulsion - Industrial Gas Turbine development continued
after World War II - Robust
- Compact
- Ability to operate on gas fuels
- No external coolant required
- Size range now 1 100 MWe
4The Basic Concept simple cycle
5Typical Cogeneration System
6Typical Industrial Cogeneration System
7Gas Turbine Cogeneration Plant
Solar Turbines
8Gas Turbine Cogeneration Plant
Solar Turbines
9Gas Turbine Cogeneration Plant
Solar Turbines
10Principles for Performance Improvement
- Power output and efficiency can be improved by
- Increasing the Firing Temperature
- Greater effect on power output but required
- New Materials
- Thermal Barrier Coatings
- Cooling of hot section components
- Increasing the Pressure Ratio
- Greater effect on efficiency but required
- New materials
- Improved Aerodynamics
11Required Developments
- Market Pressures for
- Lower Emissions
- Water or Steam Injection
- Dry Low Emissions Combustion
- Fuel Flexibility
- New combustion and fuel systems
- New coatings
- Improved Reliability Availability
- Longer Component Lives
- Intelligent Control Systems
- Condition Monitoring
12Required Developments
- Market Pressures for
- Improved Efficiency
- Improved individual component efficiencies
- Tighter tolerances, improved aerodynamics
- More complicated to manufacture
- Higher Firing Temperatures
- More exotic materials
- Reaching firing temperature limits effectiveness
of DLE - Reduced Costs
- Increased Power Density
- Higher firing temperatures new component
designs - More compact turbomachinery with lower component
costs - More highly loaded components
13The Results of Technology Development
- Improvements in design have led to
- Reduced size
- 13MW gas turbine now needs same package space as
a 6.5MW gas turbine of 1980 - Improved Efficiencies
- 35 electrical efficiency compared to 30 in 1980
- Reduced Emissions
- Single digit NOx possible on natural gas
- Further improvements possible, but incremental
14Future Possibilities
- For step change improvements, move to Complex
Cycle technologies - Combined Cycle
- Recuperated
- Intercooled Recuperated
- Integration with high temperature Fuel Cells
- Solid Oxide or Molten Carbonate
- Reheat
- Cheng Cycle
- Wet Cycles
- Humid Air Turbine (HAT) Cycles
15Combined Cycle (Brayton Rankine Cycles)
GAS TURBINE
STEAM TURBINE
16Combined Cycle
- Uses GT exhaust gases to produce steam for Steam
Turbine generator - Approximately 40 - 50 additional power
- 13MW gas turbine gives c.18.5MW in CCGT
configuration - Approximately 15 - 20 points increase in fuel
efficiency - 13MW GT of 35 electrical efficiency gives 50
efficient CCGT - Increased Capital Costs
- High pressure HRSG, Steam Turbine etc.
- Increased Space Requirements
17Recuperation and Intercooling
- Recuperation
- Uses exhaust gases to preheat combustion air
- Improves efficiency for same mass flow, but
slight power reduction - Intercooling
- Reduces the work required to compress air
- Increases power output for same mass flow but no
efficiency gains - When combined with recuperation (ICR), improves
efficiency too - Rolls Royce WR21
- Simple Cycle 13MW 35 efficiency
- Recuperated 12MW 40 efficiency
- ICR 15MW 45 efficiency
18Combined Gas Turbine / Fuel Cell Derivatives
- Can integrate gas turbines with High Temperature
Fuel Cells - Fuel flexible
- Increases power density of FC
- Offers very high electrical efficiencies
- Concept designs and pilot plant
- 200kW pilot scheme from NKK/JFE, Japan with 2000
hrs experience - 300kW plant of 57 efficiency under construction
in USA - lt 1MW scheme from Siemens Westinghouse within 2
-3 years - 40MW concept based around WR21 ICR Gas Turbine
19Gas Turbine Cogeneration - Selection Criteria
20Heat Recovery Methods
- Direct Heating
- Fluid Heating / Hot Water
- Steam Production
- Absorption Chilling
- Preheated Combustion Air
21Industries using Gas Turbine Cogeneration
- Food Processing
- Pharmaceutical
- Pulp and Paper
- Manufacturing
- Refinery
- Hospitals
- Universities
22Cogeneration Economic Factors
- Need for reliable electric and thermal Energy
- Facility Heat to Electricity Ratio of 21
- Electricity Price to Gas Price Ratio of 21
- Continuous Operation
23Gas Turbine Summary
- Simple Cycle designs are approaching their limits
- Application flexible
- Complex Cycles offer improved efficiencies and
higher power densities - More complicated designs
- Danger of becoming application specific
- Optimum component technologies may differ from
simple cycle designs - Uncertain market conditions
- Will conditions allow commercialisation of new
technologies ?
24Microturbines
- Small, high-speed generator power plants, 25
200 kWe - One moving part
- Primarily fuelled with natural gas major biogas
potential - Relatively low capital, OM costs
- Lower emissions than conventional reciprocating
engines - Several applications
- Traditional cogeneration, hospitals etc
- Generation using waste and biofuels
- Backup power
- Remote Power for those with Black Start
capability - Peak Shaving.
25Microturbines the Capstone System
- 30-60 kW power output
- Multi-fuel capability
- High cogen efficiency
- Low maintenance
- Low emissions
- 2-to-100 unit multipacking
- lt30 kW to 6 MW
- gt2,500 sold worldwide
- gt5 million operating hours
26Inside the Microturbine
Exhaust
Control panel
MicroTurbine
Air inlets
Fuel supply
0-30 0-60 kW400-480 VAC/DC
User connection bay
Digital power controller
27Deep Inside the Microturbine
- One moving part
- No coolants or lubricants
- Compact and lightweight
28WADE Key Points
- Non-profit organisation created June 2002
- Mission
- To accelerate the deployment of DE systems
worldwide - WADE is supported by
- National Cogen/DE organisations including COGEN
Portugal - Cogen/DE companies with international interests
- Caterpillar, Capstone, Solar Turbines, FuelCell
Energy, MTU, Marubeni, Primary Energy, Dalkia,
Wartsila - UN agencies
- National governments (eg US, Norway, Canada)
29WADE Network of DE Promotional Organisations
2nd (Amsterdam, 2001)
5th (Beijing, 2004
1
st
(Washington, 2000)
3rd (Delhi, 2002)
WADE Network
4th (Rio, 2003)
In train
WADE Annual International Conferences
30WADE action
- Documenting DE development and barriers
- World Survey of Decentralized Energy 2004
- National DE Surveys China, Brazil
- Promoting worldwide knowledge
- Cogeneration On Site Power Journal of
international DE industry - Annual International CHP DE Conferences
Washington (2000), Amsterdam (2001), Delhi
(2002), Rio de Janeiro (2003), Beijing (2005). - Promoting DE with international agencies, eg
World Bank institutions and UN agencies - Building international network of DE
organisations - Carbon credit development from DE