CASE STUDY 4 Strategy for integrating Renewable Energies

in small and weak island electrical grids:

Overcoming the technical challenges

Seminar

Inter-American Development Bank

June 27th, 2018

Salvador Suárez

Canary Islands Institute of Technology

Grid stability: balancing the electrical island systems

• The islands power systems have to be at equilibrium at every moment, which requires that power generation be regulated to guarantee that it always equals instantaneous electricity demand

• Power regulation of RES translates into curtailment and less operating hours of wind systems, which negatively impact the initially foreseen return on investment of these investment projects

• Since the variable generation curve profiles of RES doesn’t match the electrical demand curve of the island, curtailment of RES generation is needed to avoid excess electricity

Small non-inteconected island electric systems are more sensitive to RES variations, a critical issue affecting grid stability of small and weak island electrical system in scenarios of high RES penetration.

TECHNICAL BARRIERS TO RES

MAXIMIZING RES PENETRATION:

Electric System Land Planning Economic-Administrative issues

1- Forecasting wind and solar

5- Energy storage

Security and reliability

Strategy for maximizing RES penetration

3- Demand Management

Barriers to renewable energy penetration in Islands electric power systems

The need for enacting policies to support renewable energy is often attributed to a variety of barriers that prevent investments from occurring.

Scheduling

Market - Risk analysis

Planning

Electrical demand

Wind generation

2- Grid stability analysis

4- Distributed

generation

1 - PV AND WIND FORECASTING

MEASUREMENT STATIONS NETWORK • 23 Radiometric stations

• 33 Wind stations

WEATHER FORECAST SERVICE: to estimate the energy to be injected in the grid by photovoltaic and wind generators within a 6-96 hours time horizon (MM5, WRF).

NWP (Numerical Weather Prediction): Modells WRF y post processing with artificial intelligence techniques.

MSG Antenna 5 min Time Resolution 1,2 km Spatial Resolution

Reliable forecasting is key in the strategy for planning and scheduling

generation, meeting the criteria of preferential grid access to RES, while

ensuring secure supply.

SOLAR MAP : used for estimation of PV plant production

Wind condition measurements at 148 sites

23 Radiometric stations

WIND MAP: Wind potential for feasibility analysis of wind farms

RESOURCE ASSESSMENT: WIND, SOLAR AND BIOMASS MAP

Sistema energético actual

Voltage and frequency regulation

• Analysis of islands transmission-distribution grids capacity to handle RES

• Determine maximum admissible levels of penetration of variable and intermittent RES in small and weak island electrical grids

• Propose cost-effective actions to strengthen island grids for maximizing RES

Elaboration of mathematical models to simulate the dynamic behaviour of electrical island systems, to the constraints that limit the penetration RES.

2 - GRID STABILITY ANALYSIS

Analysis of the Lanzarote-Fuerteventura electrical system

Modelling on PSS®E v32.

Modelling on PSAT Stationary and dynamic stability studies of the electrical grid to realistically asses the RES penetration limits, and cost effective solutions to reinforce the grids

Punta Grande 244,24 MW Diésel and gas turbine

Isladelanzarote.com

fuerteventuradiario.com

Las Salinas 187,43 MW Diésel and gas turbine

Lanzarote:

Peak laod

170,30 MW

Fuerteventura

Peak load

123,80 MW

Interconnection

66 kV Playa Blanca – Corralejo

132 kV Playa Blanca – La Oliva

3 - DEMAND SIDE MANAGEMENT (DSM)

• In scenarios of high RES penetration, time shifting the operation on non-critical deferrable loads, could contribute to reduce the need for curtailment of wind farms and PV installations, improving their financial feasibility

• DSM on potential deferrable loads (time shifting, load shedding) can lower the CAPEX and OPEX of the global island electrical system from the supply side

• DSM, as a tool of the TSO (Transport System Operator - REE) to control manageable loads, is an essential element in the strategy for peak-shaving and for balancing the intermittent supply on the grid from RES. Key issues in the strategy towards maximizing RES

RO

TSO

DSM

TSO = REE

RO

DEMAND MANAGEMENT

30% of oil consumed in the internal market goes to the road transport sector.

Electric vehicle are manageable loads with potential to become an instrument to promote greater RES penetration

ELECTRIC MOBILITY

OTHER MANAGEABLE LOADS

• Domestic Hot Water in the

residential sector represents

30-40 % of electricity

demand.

• The residential sector represents 30 % of electricity demand in the islands

Sea-water 430,000 m³/d 167 plants

Brackish-water 150,000 m³/d 146 plants

DSM on non-critical deferrable loads is a key issues for peak-shaving and for balancing the grid. An essential element in the strategy towards maximizing variable and intermittent RES generation.

WATER DESALINATION and distribution consumes 20% of electricity.

FORECAST ELECTRICITY DEMAND OF EVs 2030

10 25 51 86

126 174

230 298

378

474

587

721

880

0 GWh

100 GWh

200 GWh

300 GWh

400 GWh

500 GWh

600 GWh

700 GWh

800 GWh

900 GWh

1.000 GWh

In 2030 it will be necessary to provide electricity to 300,000 EVs aprox. 880 GWh.

• Slow 2,3 – 3,6 kW

• Medium 22 kW

• Fast 44 - 50 kW

0

50.000

100.000

150.000

200.000

250.000

300.000

350.000300.000 EVs

The energy storage capacity makes EVs a key element for the management of renewable energy. By controlling the charging process of the batteries, electric vehicles can contribute to the flattening of the electricity demand curve in small island systems.

• Transmission infrastructures are costly and a difficult to install.

• They account for losses in energy of as much as 10 %.

Hybrid microgrids:

• Eliminate the need for new transmission infrastructure

• Shortens the distance from electricity generation to consumption, reducing energy losses along the way.

• The increased capital cost of RES and batteries is quickly repaid by the l savings in operating costs and environment impacts (CO2 emissions).

• The autonomous energy system can easily be expanded by adding power generators when the demand rises.

4- DISTRIBUTED GENERATION - MICROGRID

TYPES OF MICROGRIDS

OFF-GRID HYBRID MICROGRIDS

Systems designed to cover the needs for power quality service of users who have no access to an electrical grid, or prefer to be completely independent of grid power.

GRID TIED HYBRID MICROGRIDS The microgrid remains connected to the electric utility grid at all times. The grid provides the balance of power if there is a RES shortfall. Any excess power from the microgrid RES generation is routed into the electric utility grid.

Power generated from grid connected microgrids can support and improve the efficiency of the larger power grid operation by providing to the grid valuable ancillary services, including:

• Capacity support for handling peak demand through reserve power, both spinning and non-Spinning Reserves

• Voltage support and frequency regulation

• Demand response, real-time price response

• Black Start capability support

• Reactive power and voltage control

MICROGRID LA GRACIOSA

• High RES penetration Microgrid combining photovoltaic, energy storage (batteries), but maintaining the connection to the grid.

• The objective is to minimize power flow in the submarine interconnection with neighbouring Lanzarote, and maximizing energy self sufficiency of La Graciosa.

Batteries

Control and power

conditioning unit Loads

658 permanent residents 342 houses

Battery

Substation 1

Substation 2

PV (MV)

PV (LV)

LOAD LOAD

PV (LV)

Batteries

Control and power

conditioning unit Loads

Lanzarote Power System

Submarine Connection

La Graciosa Microgrid

High RES Microgrid combining PV, energy storage (batteries), minimizing need for diesel backup

MICROGRID LA GRACIOSA

Computer model for the emulation was developed for testing SiNGULAR tools

Design and optimization of high RES penetration microgrids. Integration of wind-PV-batteries-diesel for grid connected operation, and for off-grid stand-alone applications.

Distributed generation lab R&D lines

• Assessment of new approaches for electric grid control. Load and storage Management

• Communication protocol interfaces aimed at improving management and control strategies (ICT’s)

• Distributed Generation interconnection elements testing

• Strategies for the integration of distributed generation sources (solar, wind …)

ITC’s MICROGRID TESTING PLATFOTM

Pilares del nuevo paradigma – Almacenamiento de energía

- Wind–Pumped–Hydro

- Compressed air

- Batteries

- Flywheels

- Ultracapacitors

- Hydrogen

- Thermo-chemical cycles

Energy storage are essential to maximize RES penetration in weak electrical networks.

5- ENERGY STORAGE

• Solutions to store surplus RES in valley hours to feed into the grid in peak demand.

• A suitable public supported retribution mechanisms would have to be implemented so that part of the benefit to the electrical system is transferred to energy storage developers, to compensate their high investment cost and their role in grid balancing

STORAGE VALUE

• Load leveling

• Back-up energy to stabilizing voltage and frequency regulation

• Balance of RES

• Diesel reduction

• Improved power quality

• System reliability

Energy storage provide the following value services:

Energy storage solutions might seem incredibly costly if all you want to do is store excess energy from RES, but once you factor in the full range of other services provided, it soon seems much more attractive.

The cost of energy is relative to its availability and convenience, and most people are willing to pay much more for energy when it’s not readily available.

Typical “D” alkaline batteries stores about 0.021 kWh of energy (14 mAh at 1.5 volts). At a cost of about 1 €/cell, the cost of energy is about 47 €/kWh. Up to 475 times what most pay for utility-supplied electricity 0.10 €/kWh.

Energy recovery from waste

Energy recovery is a key element in the fight to reduce waste volumes that accumulate in the landfills of the archipelago.

Biomethane: biogas with 50% CH4 has a LHV about 5

kWh / Nm³. To improve the heating value of biogas we

must eliminate CO2.

Biodigestors: convert organic fraction of waste into usable products: Biogas (methane 40-75%) and fertilizer :

Energy efficiency • Reduction of energy intensity: decrease the amount of (primary)

energy needed to produce one unit of GDP

• Environmental Impact of CO2 emissions

• Increase efficiency in industry, tourist and residential sectors

• Reduce energy consumption in Public buildings

SOLAR THERMAL COLLECTORS TESTING LAB

(LABSOL)

• Optimization of systems and components used in solar energy installations

• Contribute to improve the quality in the solar energy sector through the dissemination of results and lessons learned

• Provide the necessary technical support to companies involved in the field of solar thermal.

OBJECTIVES

•UNE-EN ISO/IEC 17025:2005

•UNE-EN 12975-2:2006

• Exposure tests

• Internal Thermal Shock

• External Thermal Shock

• High-Temperature withstand

• Internal pressure

• Rain penetration

TESTS • Mechanical load

• Steady-state and external output

• Angle of incidence modifier

• Materials Corrosion

• Effective thermal capability and time constant

20

European island pilots in

SINGULAR project

Pilot islands Tools validated

Crete (Greece) Forecasting Scheduling Power Analysis Demand Response

Sao Miguel (Azores/Portugal) Forecasting Scheduling Power Analysis Planning

Braila/Scanteiesti (Romania) Forecasting Power Analysis

Pantelleria (Italy) Forecasting Power Analysis

La Graciosa (Canary Islands/Spain) Forecasting Storage Management Planning

El Hierro (Canary Islands/Spain) Forecasting

TILOS ISLAND - GREECE

• Residents ~ 500

• Peak load ~ 750 kW

• Electricity supplied from neighboring Kos

• Frequent and long-lasting black-outs

Objective: The development of a prototype storage system based on Sodium Nickel

Battery, that will support the operation of a high RES penetration smart microgrid:

The microgrid will operate both stand-

alone and grid-connected, while

optimizing the interoperability of the

microgrid components (RES generation,

energy storage and deferrable loads), by

integrating smart meters, demand side

management and distributed residential

heat storage.

The solution will contribute to

• Higher RES penetration

• Grid stability

• Ancillary services to the main grid

PROJECT STRUCTURE

Preliminary simulations and

grid study

• Energy balance

• Power analysis

Wind, solar and

load forecasting

RES2H2 project (RES – H2 Microgrid)

Demonstration project on H2 as an energy storage, for stabilizing a stand-alone

microgris in high RES penetration scenarios

• Wind turbine: 225 kW

• High pressure alkaline electrolizer (25 bar): 55 kW

Nominal production: 11 Nm3H2/h

• H2 storage: 500 Nm3 at 25 bar

• H2 purification unit

• Fuel cells: 30 kW

• RO desalination plant: 40 kW

1 atm

3 kWh/Nm³H2

0 ºC

Fuel cells 1.5 kWh

1.5 kWh

Heating power

Heat

Eléctricity

25 bar

η = 50 %

89,3 g of H2

89.3 g de H 2

HYDROGEN ENERGY BALANCE

Electrolizador

WATER

HYDROGEN (H2)

ELECTRICITY

Compressor

4.5 kWh/Nm³H2 0.8 kg H2O/Nm³H2

HYDROGEN at ITC: Most relevant RES –

H2 projects

With 1.025 MW of wind-power

(PECAN: target 2015), and by using

energy surpluses from valley hours,

H2 could be produced to run 600

urban buses.

HYDROHYBRID

RES2H2 H2 energy vector

H2 automotive fuel

HYDROBUS

Practical experiences allowing ITC to

progress on the H2 technologies learning

curve

Capacity building through courses at all levels, for specialized training in design, installation, operation and maintenance of RES systems, to improve the qualification and improve the productivity of technical staff.

TRAINING ON RES AND ENERGY EFFICIENCY

Training is a key issue in an strategy for overcoming some of the most important barriers to RES development.

PV TRAINING KIT

Easy to transport

MOBILE HYBRID WIND-SOLAR TRAINING KIT

WIND TRAINING KIT

ENERGY TRAINING KITS

Experience on RES has been applied in the design of equipment to support training courses on installation, operation and maintenance of RES systems.

Morocco •Rural electrification •RES planning

Mauritania •Wind map •Energy planning •Canary Islnads park

Cape Verde •Rural electrification •RES planning

ECOWAS (300 million inhabitants)

Support to ECREEE in the transferring of clean energy technologies to promote sustainable development in Benin - Burkina Faso - Cape Verde - Ivory Coast – Gambia - Ghana - Guinea - Guinea Bissau - Liberia – Mali - Niger - Nigeria - Sierra Leone - Togo - Senegal

More than 15 years’ experience designing and installing RES-hybrid systems in rural areas of these countries.

TRANSFERING OF CLEAN ENERGY TECHNOLOGIES TO LESS DEVELOPED COUNTRIES

Projects that will contribute to increase RES penetration in European Islands in all the energy value chain

Generation

Energy Storage

Energy Efficiency

Electric vehicles

Water desalination

Reversible pump-hydro

Batteries

Hydrogen

Wind, solar, Wave, Geothermal, Biomass, hibrid (wind-diesel)

Final consumption

Microgrids, district heating and cooling, etc.

IDENTIFYING POTENTIAL BANKABLE PROJECTS

Distribution

Primary sectors Industry Services Residential

Needed public support for overcoming existing barriers to RES in Islands

• High cost of the technologies

• High upfront payment and relative long payback periods

• High financing costs

IDB could contribute to bankability of RES projects in Caribbean island regions though

• Favourable loans

• Capital subsidies

• Tariff support schemes

Promotion of highly visible demonstration projects in European Islands

Existing barriers to RES include technical, regulatory/administrative, marketing, but European support should focuss in existing financial barries to private investment in RES projects

Local island governments can contribute through:

• Simplification and adaptation of administrative procedures for new energy installations (incl. electrical infrastructure)

• Introducing regulatory frameworks that favour RES

• Adapt territorial

SUMMARY

• A strategic element for increasing RES is Demand Management of grid connected deferrable electrical loads, to increase/decrease overall electric power demand of the island, as a function of available wind and PV power generation.

• The small and weak grids limit the penetration of variable and intermittent RES. Island system operators faces a growing challenge of bringing balance to electricity supply and demand, in a context of rapid growth of non-dispatchable RES power generation.

• Most RES projects involve technologies that lack the competitive maturity of fossil fuel based technologies. To attract private investors regional, national and multilateral institutions public support is needed.

• RES powered electric vehicles will contribute to achieve full decarbonisation of road transport in islands, but EVs are also energy assets that have value as non-critical electrical loads that could be shifted in time to compensate the variability of RES power generation.

• Energy storage is key for increasing RES. For a business case to be made for energy storage systems as an instrument used by the TSO for for grid balancing and maximizing RES in islands, part of the benefits from higher RES should go to reward energy storage, to off-set their high investment cost).

Thank you

Salvador Suárez

Canary Islands Institute of Technology

ssuarez@itccanarias.org