Smart Grids implemented on Scottish islands

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? [email protected]

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