simple wind-diesel concept with high wind penetration in cape verde
DESCRIPTION
Simple wind-diesel concept with high wind penetration in Cape Verde. Per Nørgård, Risø DTU, Denmark, [email protected] João Fonseca, Electra, Cabo Verde, [email protected]. Cabo Verde. Independent (from Portugal) in 1955 Population: 500 000 at 10 islands Islands in study: Santiago - PowerPoint PPT PresentationTRANSCRIPT
Simple wind-diesel conceptwith high wind penetrationin Cape Verde
Per Nørgård, Risø DTU, Denmark, [email protected]ão Fonseca, Electra, Cabo Verde, [email protected]
EWEC 2009Per Nørgård2 Risø DTU, Technical University of Denmark
Cabo Verde
•Independent (from Portugal) in 1955•Population: 500 000 at 10 islands•Islands in study:
SantiagoSão VicenteSal(Boa Vista)
EWEC 2009Per Nørgård3 Risø DTU, Technical University of Denmark
Cabo Verde
Risø DTU as Technical Consultant• for InfraCo (international project
developer)• in collaboration with Electra (local
power utility company)
Power generation based on diesel generationExcellent wind conditions
• High average wind speeds most of the year
• Very constant wind• Low extreme wind speed
EWEC 2009Per Nørgård4 Risø DTU, Technical University of Denmark
Growing demand
0
10
20
30
40
50
60
2000 2005 2010 2015 2020
Pow
er (M
W)
Year
Max power load
Santiago São Vicente Sal Boa Vista
EWEC 2009Per Nørgård5 Risø DTU, Technical University of Denmark
IPSYSan energy system simulation tool
Characteristics• Semi-static time series simulation
(minutes time steps)• Includes storage and memory
functionalities• Designed for mixed energy
systems• Performs energy balances and
load flow analysis (power systems)
• Handles advanced and distributed control
• Developed by Risø DTU
EWEC 2009Per Nørgård6 Risø DTU, Technical University of Denmark
Simplified single line diagrams
EWEC 2009Per Nørgård7 Risø DTU, Technical University of Denmark
Operation strategy
1. Minimum continuous diesel load
2. Minimum instantaneous diesel load
3. Minimum spinning reserve diesel capacity
4. Minimum diesel capacity5. Minimum number of diesel
generator units6. Minimum diesel operation
time
• Minimum continuous load of the diesel engines: 30% (optional 50%).
• To prevent the diesel engines from sooting up at low load.
• The wind power generation may be limited to fulfil this condition.
EWEC 2009Per Nørgård8 Risø DTU, Technical University of Denmark
Operation strategy
1. Minimum continuous diesel load
2. Minimum instantaneous diesel load
3. Minimum spinning reserve diesel capacity
4. Minimum diesel capacity5. Minimum number of diesel
generator units6. Minimum diesel operation
time
• Minimum instantaneous load of the diesel engines: 10%.
• To prevent for negative load of the diesel generators.
EWEC 2009Per Nørgård9 Risø DTU, Technical University of Denmark
Operation strategy
1. Minimum continuous diesel load
2. Minimum instantaneous diesel load
3. Minimum spinning reserve diesel capacity
4. Minimum diesel capacity5. Minimum number of diesel
generator units6. Minimum diesel operation
time
• Minimum spinning reserve diesel capacity connected to the grid:
200% of the observed fluctuation of the diesel load within the last hour andminimum 50% of the actual diesel load (if possible).
• To be prepared for the fluctuations in the wind power and in the load.
EWEC 2009Per Nørgård10 Risø DTU, Technical University of Denmark
Operation strategy
1. Minimum continuous diesel load
2. Minimum instantaneous diesel load
3. Minimum spinning reserve diesel capacity
4. Minimum diesel capacity5. Minimum number of diesel
generator units6. Minimum diesel operation
time
• Minimum diesel capacity connected to the grid:
2 times the wind capacity connected to the grid.
• To ensure dynamic stability of the system.
• @ low load + high wind:wind turbines are shut down-> diesel generators shut down
EWEC 2009Per Nørgård11 Risø DTU, Technical University of Denmark
Operation strategy
1. Minimum continuous diesel load
2. Minimum instantaneous diesel load
3. Minimum spinning reserve diesel capacity
4. Minimum diesel capacity5. Minimum number of diesel
generator units6. Minimum diesel operation
time
• Minimum number of diesel generator units connected to the grid:
2• Not to rely on a single diesel
generator unit.
EWEC 2009Per Nørgård12 Risø DTU, Technical University of Denmark
Operation strategy
1. Minimum continuous diesel load
2. Minimum instantaneous diesel load
3. Minimum spinning reserve diesel capacity
4. Minimum diesel capacity5. Minimum number of diesel
generator units6. Minimum diesel operation
time
• Minimum operation time of a diesel engine:
4 hours.• To limit the number of start / stop
of the diesel engines.
EWEC 2009Per Nørgård13 Risø DTU, Technical University of Denmark
Load profiles(3x3 days)
Load profiles
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
0 1 2 3 4 5 6 7 8 9
Time (days)
Pow
er (M
W)
SantiagoSão VicenteSal
EWEC 2009Per Nørgård14 Risø DTU, Technical University of Denmark
Seasonal variation of wind
5
6
7
8
9
10
11
12
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan
Mon
thly
ave
rage
win
d sp
eed
@ 3
1m (m
/s)
Flamengo
Filipe
Palmeira
EWEC 2009Per Nørgård15 Risø DTU, Technical University of Denmark
IPSYS results (Sao Vicente)
EWEC 2009Per Nørgård16 Risø DTU, Technical University of Denmark
Summary of results
2009 Santiago Sao Vicente SalMin load 16 6 7 MWMax load 32 12 16 MWEnergy consumption 210 70 90 GWh/yDiesel capacity 44 16 20 MWWind capacity 10 6 8 MWPotential wind energy 35 28 33 GWh/yNot utilised wind energy 0 3 3 GWh/yNot utilised wind energy 0% 11% 9%Wind power penetration 17% 36% 33%Avoided diesel fuel 7 5 6 kt/y
EWEC 2009Per Nørgård17 Risø DTU, Technical University of Denmark
Not utilised wind energy
1 p.u.: 20% wind energy penetration
Not utilsed wind power
0%
2%
4%
6%
8%
10%
0.0 1.0 2.0 3.0
Wind power capacity (p.u.)
Not
util
ised
win
d po
wer
(%)
Sal Sao Vicente Santiago
EWEC 2009Per Nørgård18 Risø DTU, Technical University of Denmark
Avoided diesel fuel
1 p.u.: 20% wind energy penetration
100
150
200
250
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Wind power (p.u.)
Rel
ativ
e fu
el c
onsu
mpt
ion
(ton/
MW
h)
-60%
-40%
-20%
0%
Fuel
diff
eren
ce (%
) SantiagoSalSao VicenteSantiagoSalSao Vicente
EWEC 2009Per Nørgård19 Risø DTU, Technical University of Denmark
Minimum diesel load (2012)
Diesel min load Wind power Wind penetration Not utilsed wind% MW % % kt/y
Santiago 30% 8,5 14% 0% -8,34 -14%50% 8,5 14% 0% -8,34 -14%
Sao Vicente 30% 6,0 40% 4% -5,32 -34%50% 6,0 31% 24% -4,07 -26%
Sal 30% 8,3 26% 1% -6,51 -24%50% 8,3 25% 4% -6,29 -23%
Fuel diff
EWEC 2009Per Nørgård20 Risø DTU, Technical University of Denmark
PPA – Power Purchase Agreement
Minimum wind energy level’take & pay’ @ high tariff
• Motivates wind power operatorto maximise production
Additional wind energy@ low tariff
• Motivates diesel operatorto optimise operation
EWEC 2009Per Nørgård21 Risø DTU, Technical University of Denmark
Conclusions
• The most critical operation parameter is the minimum diesel load.
• Even at 40% wind energy penetration, the not utilised wind energy is ’only’ 10%.
• 20% ’overinvestment’ in wind power capacity is proposed
22 MW -> 28 MW -> 0..10% not utilised wind energy.
• This seems economically feasible at 5% reduced generation cost ($/kWh), with the expected demand growth.