Download pdf - Frits Ogg the windturbines of st helena benefits and impacts balancing of power and power quality with medium size windturbines ddefww

WSSW 2014The windturbines of St. Helena- benefits and

impacts, balancing of power and power quality with medium size windturbines

5th World Summit for Small Wind 2014 (WSSW)

Frits Ogg O2G Sustainable Energy Solutions

The Netherlands

Husum 21 march 2014

The windturbines of St. Helena - WSSW 2014 - Frits Ogg 2

● St. Helena● Previous● New situation● What is medium size?● WES, WES Hybrid & BBalancing of power● Benefits● Power Quality● Actual developments

Content


©St Helena Tourism Office


st. Helena● Remote Island, South Atlantic

Ocean● 4000 Inhabitants● Sovereign British territory● Only accessible by boat –

Ascencion, Cape Town● Boat transport capacity limitated● Until 2016 (Airport ready)● Steep and challenging terrain


Previous● 6 Aging diesel generators● 6 windturbines● 11 kV distribution network● Average hourly demand 1 MW

● Maintaining power supply during installation


New situation● Replacing 4 existing

generators (3 Cat 3516B & 1 Cat 3508B)

● Extensive control system● IMC Worldwide – Senergy –

Barloworld Power● New 11 kV switchgear● More Windturbines● Dec 2012 system operates

reliable, operators trained


Medium windturbines~ 50 kW => ~ 300 kW


WES & Windenergy● 1980 Dutch wind turbine pioneer Henk Lagerwey● 2003 Lagerwey went out of business● 2004 Wind Energy Solution (WES) is the owner of

Lagerwey’s exclusive rights, drawings and engineering files

● The original Lagerwey LW wind turbine was installed mainly for farmers in the Netherlands.

● WES improved the mechanical control system and replaced power conversion with modern, remote-monitored technology.


Hybrid technology


Controlling the maximum power output●Primary Control: based on grid frequency B(Passive pitching)●Secondary Control: based on communication B(Optical, Ethernet etc.)

WES HYBRID CONCEPT

Passive Pitching

●Maximum rotor speed limitation●Reduced power production is possible


●Fly wheel needed to maintain a stable frequency●Dump load needed to shed the excess energy generated●Wind power penetration is usually not larger than 30%●An external power management system is needed to Bcontrol the whole system

Conventional System:

●Continuous and Bimmediate output control●No external management Bsystem, fly wheel and Bdump loads needed●Excess energy can be Bused to power the diesel Bgenerator

WES Hybrid System:


Grid Power Balance 1

● Grid power balance is 50 Hz or 60 Hz● Higher grid frequency when consumption is less than

production● The Automatic Voltage Regulator (AVR) of the diesel

generator measures the changing grid frequency and will decrease the output

● When the frequency goes beyond its own control boundaries the wind turbine will limit its output

● The wind energy potential at that moment will not be (fully) converted into electricity


Grid Power Balance 2● Less energy is fed into the grid, the demand and supply

will become balanced again and the frequency will decrease

● The reduction of the wind energy supply will continue until the required grid frequency has been reached

● The frequency will drop below the required level when the demand for energy is greater than the diesel generator and the wind turbine can supply at that moment

● When a number of users are suddenly switching on or when the wind speed drops, the diesel generator will automatically inject extra fuel to meet the extra energy demand


Benefits & Impact● Since 1998 three turbines have been

operating on the island and can deliver 600.000kWh/year to the local grid.

● During the 15 or so years since these turbines were installed, the use of electricity on the island has doubled.

● Another three turbines were added in 2009.

● WES has now sold another six turbines to the island, that are installed now. The estimated pay-back time for the turbines is 2-4 years.

Deadwood plain st.Helena


SCADA(Supervisory Control And Data Acquisition)

Benefits & Impact 2● The diesel station is controllingBthe maximum power output of Bthe wind turbines● Up to 60% of the electrical Bpower has been supplied by the Bwind turbines● With the addition of 6 turbines Bthe target is to reach a wind Bpenetration level of 80% or more

Diesel Saving● 1L Diesel = 36 MJ/l = 10 kWh/l● Efficiency of diesel gen-set = 30%● 1L Diesel = 3 kWh● 1L Diesel = € 1,-● 1 kWh = € 0,33

● 1 x WES80 at 18m tower producing about BB200.000 kWh/year = saving about 65.000 l/year


Power Quality – harmonics● Switching electronics cause vulnerabilities on

an AC grid = a concerning development● One of these vulnerabilities are harmonics● Harmonics are not only produced by PV and

Windenergy converters but also by LED drivers, computers and motor control devices

● Harmonics are to be prevented / filtered


Actual situation

● Installing 6 new turbines on st. Helena● Article (Windtech – international) medium

turbines● Actual overview manufacturers medium

turbines● Overview Power balancing systems


Actual Situation 2


Actual Situation 3


Actual Situation 4


Actual Situation 5


Actual Situation 6


Thank you for your attention

[email protected] www.o2g.nl@fishfrogg skype: frits.ogg

More information:Www.windenergysolutions.nl Www.windtech-international.comWww.sthelenatourism.comWww.sainthelena.gov.com Www.barloworld.comWww.senergy.comWww.small-wind.org/forum

Thanks to WES, Barloworld, BigPartnership (Jamie MacDonald) and the tourism office of st.Helena for the help and the pictures.

My Ham Radio call is PA2LIA

http://www.o2g.nl/

http://Www.windenergysolutions.nl/

http://Www.windtech-international.com/

http://Www.sthelenatourism.com/

http://Www.sainthelena.gov.com/

http://Www.barloworld.com/

http://Www.senergy.com/

http://Www.small-wind.org/forum