Smart Grids implemented on Scottish islands Ruth Kemsley Senergy Econnect Ltd United Kingdom
Senergy Econnect
Part of Senergy Alternative Energy Offices around the world Electrical engineering All forms of renewables 50% of all wind commissioned in Great Britain Smart Grid and Active Network technology group
Overview
1
Practical application of Smart Grid technologies in island power systems
2
Wider applications of this Smart Grid knowledge
3
Extension to renewable electric transport
Off-grid islands in Scotland
Smart Grids
Smart Grids Features distributed and diverse generation high usage of renewables variable energy tariffs load management energy storage communications
All implemented (at small scale) on Scottish islands All these islands have achieved 100% renewable operation
Fair Isle, Shetland Distributed load management 1982 60kW wind turbine with diesel back-up bespoke control system system frequency controlled by heating loads distributed around island each house has 2 circuits - "heating" (cheaper) and "service" (more expensive)
1998 100kW wind turbine added
2009 operating successfully - frequent use of 100% wind islanders considering adding energy storage to improve operability
Isle of Muck, Small Isles Central control with radio communications 1999 2 x 25kW Vergnet wind turbines with diesel back-up battery energy storage PLC-based control and generator scheduling radio-controlled load and tariff management 3.3kV network
2008 feasibility study to look at increasing battery capacity and improving operability
Isle of Rum, Small Isles Frequency-based load management Early 20th century DC hydro generator and accumulator energy storage DC supply to Kinloch Castle
1970s 2nd hydro turbine added and AC distribution network
1984 system refurbishment central heating loads in Castle absorb surplus hydro energy bespoke heating load controller
1997 load-shedding Powaplugs added to prevent system overloads
2008 feasibility and design for addition of energy storage and increased hydro capacity
Isle of Rum
dam and pipeline
hydro generators
Isle of Rum - typical operation
30
Heating load controller
25
Kinloch village + Castle
20
kW
Total hydro output
Kinloch Castle
15
10 Kinloch village
5 Kinloch village 0 15 Jan 12:00
16 Jan 00:00
16 Jan 12:00
17 Jan 00:00
17 Jan 12:00
18 Jan 00:00
18 Jan 12:00
19 Jan 00:00
19 Jan 12:00
Island of Foula, Shetland Distributed generation and load management 1980s-90s wind / hydro / diesel bespoke control system using cable communications frequency-based load management variable tariffs 3.3kV distribution network
2007-8 refurbished hydro, distribution network, load management Sunny Island inverter system battery energy storage PV / diesel frequency-based generator management (wind)
Island of Foula - 2009
Island of Foula - 2009 3.3kV T2
T3
T4
T5
T6
T8
T7 School
T9
DISTRIBUTION TRANSFORMERS
400V PHOTOVOLTAICS
3.3kV cable network
19.2kWp
G
~
no change to HV modified LV protection
15kW
HYDRO
~
Revised renewables-based system energy storage planning issues with wind turbines increase use of hydro resource addition of PV for summer months frequency-based power regulation revised demand-side management diesel generator back-up
SUNNY BOY INVERTERS
= CHANGEOVER UNIT
18kW nom.
~
~
30kW
30kW
DIESEL GENERATORS
MAIN POWERHOUSE
SUNNY ISLAND INVERTERS
33kW nom BATTERIES
140 kWh (C100)
~
=
Isle of Eigg, Small Isles Early 20th century Pier hydro
~2002 upgraded Pier hydro Kildonnan hydro local LV networks LAIG
2007-8
POWERHOUSE KILDONNAN WIND FARM
PIER
Laig hydro refurbished old hydros 11km 3.3kV cable network Sunny Island system with battery energy storage PV / diesel / wind frequency-based generator and load management
Demand / generation profiles Evaluating existing energy and power demand Estimating future demand growth in number of consumers increased supply period (24-hour power) increased range of consumer goods possible use of renewable electrical heating (demand-side management) new technologies (e.g. electric vehicle charging)
Estimating generation output annual / monthly / daily allowing for variations
Issues and technologies Connecting renewables into electrical system Foula, Eigg, Rum, Fair Isle - AC connected - more flexible Muck - DC connected - generation close to batteries
Managing the power balance variable renewable input insufficient or surplus renewable power energy storage - hydro storage, batteries, diesel fuel (!) integrating battery inverter control with generator control load management
Controlling voltage generator / inverter control careful system design
Issues and technologies System management, operation and support significant community involvement (more than on mainland) robustness, reliability, and affordability are key to success remote support from equipment suppliers is essential
Metering manual meter reading switching between multiple meters (frequency or radio) to change tariff Smart Meters more expensive, but costs now falling
Load management systems without energy storage need to make maximum use of available renewables even systems with energy storage sometimes have surplus renewable power can help to utilise surplus power can also reduce peak power demand and avoid energisation problems
Applying these Smart Grid techniques Distributed renewable generation output needs to be controllable / constrainable to integrate with grid at high % renewable penetration use simple and autonomous generator control as much as possible
Load management helps with integration of variable renewable sources control signalling required - cannot use system frequency on interconnected grids - communications systems needed need to incentivise to encourage consumers to engage
Extending use of renewable electricity Electric vehicles not a "bonus" load - need to be charged need to size renewable power system for charging can vehicle charging be included in demand-side management? typical vehicle storage values comparable with island battery capacities
Electric boats? distances on islands are often small distances to islands are large and ferry / transport fuel costs are high
Summary
1 2
Small island power systems in Scotland have already: implemented a wide variety of Smart Grid technologies achieved high usage of renewable energy learned useful lessons from their experience
The Smart Grid knowledge gained: can be applied to mainland grid situations will help to improve sustainable energy use may need to be adapted in some cases
Renewable electric transport:
3
would significantly improve economic and environmental sustainability would provide most benefits in marine transport cost savings
Thank you for listening Any questions?
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References & further information http://www.fairisle.org.uk/FIECo/index.htm www.windandsun.co.uk/Projects/foula.htm www.windandsun.co.uk/Projects/eigg.htm http://www.smallwindindustry.org/fileadmin/ewea_documents/documents/proje cts/swiis/track_records/050511MUCKisland.pdf www.senergyworld.com/products/productsandservices/senergyalternatives/ec onnect/econnectproducts/islandgrids www.senergyworld.com/products/productsandservices/senergyalternatives/ec onnect/econnectproducts/powaplug
