Energy Storage and the Built Environment Steve Saunders Associate Director Arup t +44 (0)113 242 8498 steve.saunders@arup.com www.arup.com
the creative force behind many of the world's most innovative projects founded in 1946 employee owned ~12,000 staff ~ 1B turnover 2
Why are we here? Activities cover a wide range of applications High energy usage Improve renewable energy offering Waste Incineration Waste heat recovery We are technology neutral Embedded Generation
4 Electricity Storage
Energy storage in the built environment Historically, storage of heat (and cold) has been incorporated in buildings infrastructure. Examples range from: Hot water storage tanks and off-peak storage heaters Phase change heat stores serving HVAC in large and/or specialist buildings Electricity storage has tended to be confined to UPS systems or small off-grid applications 5
Why increased focus on electricity storage? Source: National Grid 6
How can storage help? Energy System Need Required Discharge Time Frame Required Storage Capacity Shift generated energy to when it is needed Minutes - Hours kw - MW Peaking plant services Hours MW Load following to increase the efficiency of thermal generation Reserve capacity if usual electric supply is unavailable Maintain frequency / voltage following a large disturbance Mitigate system congestion during periods of peak demand Minutes - Hours Hours Milliseconds - Seconds Hours MW kw - MW MW kw - MW Delaying or avoiding distribution system upgrades Hours kw - MW 7
Grid Stabilisation Storage applications in the grid Storage Transmission Sub Station Transformers Generation Storage Distribution Renewable storage Peak load relief Storage Storage UPS and Arbitrage Commercial and industrial customers Residential customers Storage Domestic Arbitrage 8
Modes of Energy Storage
Sodium Sulphur (NaS) Batteries Technology Description A sodium sulphur battery is a molten state battery with sodium (Na) and sulphur (S) as the energy carrier. Applications There are over 300 grid applications of NaS batteries worldwide. Can be used for many grid applications such as: Power quality applications and the integration of renewable energy sources. 34MW of NaS batteries have been integrated to the Futamata wind farm in Japan. Advantages High energy density Long life cycle Quick response Disadvantages Heating loss Safety issues 10
NaS (Sodium Sulphur) Source: AEP NAP 11
Lithium ion (Li-ion) Batteries Technology Description Li-ion batteries are a type of rechargeable battery which are powering the current class of electric vehicles. Applications Frequency regulation, voltage regulation and the integration of renewable energy sources. There are limited worldwide commercial installations to date. An example being a 20MW installation in Johnson City, NY, USA to provide regulation services. Advantages High energy density High discharge cycles High efficiency Disadvantages Cost Negative effects of overcharging/over discharging Self discharge 12
Flow Batteries Technology Description Flow batteries are a rechargeable battery using two liquid electrolytes stored in tanks as the energy carriers. Applications Time shifting, standby power and the integration of renewable energy sources. There are limited worldwide commercial installations to date. A 200kW flow battery was used to store renewable energy from the Huxley Hill Wind Farm in Tasmania. Advantages Withstand high depths of discharge Large number of charge/discharge cycles Virtually unlimited capacity Disadvantages Low energy density Not commercially mature 13
Compressed Air Energy Storage (CAES) Technology Description CAES involves compressing and storing air in order to store energy. Applications Worldwide, there is approximately 400 MW of CAES capacity installed. This capacity comprises of a 290 MW scheme in Germany and a 110 MW scheme in the USA. CAES is mainly suited to applications where a large quantity of energy is needed. CAES is also particularity suited to balancing variable renewable loads. Advantages Rapid start up times The mechanical system is extremely simple Longer asset life than technologies such as batteries Disadvantages Requires fuel Low efficiency Geographically constrained 14
CAES (Compressed Air Energy Storage) Source: US DoE 15
16 Liquid Air Energy Storage
Pumped Hydro Energy Storage (PHES) Technology Description Pumped storage hydro is currently the most established utility scale method for energy storage with approximately 99% of the world s grid energy storage being pumped storage. Applications Pumped storage is commonly used for peak load generation, but can also be used for black starting electricity grids in the event of a complete system failure and for providing fast reserve response for grid frequency control. Advantages Mature large scale technology Large power and energy capacity Fast response times Disadvantages Geographically constrained Away from demand centres 17
Pumped Storage Hydro (PSH) Source: Scottish & Southern Energy 18
Flywheels Technology Description Flywheel energy storage makes use of the mechanical inertia contained within a rotating flywheel in order to store energy. Applications Suited to improving power quality by smoothing fluctuations in generation, as opposed to having long output durations. There are limited grid scale installations to date, an example being a 20 MW installation at Stephentown, New York, USA. Advantages Rapid response times Effective way of maintaining power quality Virtually unlimited number of charge/discharge cycles Disadvantages Variable speed rotation as energy is extracted High price 19
Storage technologies Developed Development status of storage technologies Batteries ( lead acid, NiCd ) Pumped hydro Li - ion NaS Liquid Air Compressed air Cryogenics Superconducting Micro CAES Hydrogen storage kw 100 kw MW 10 MW 100 MW Note: the width of the bar indicates storage capacity Power rating
Typical Storage development process Feasibility Development Deployment Evaluation Strategy Site Selection Issue Identification Size + Capacity Technology Selection Business Case Environmental Assessment Socioeconomic Evaluation Stakeholder Management Detailed Design Economics, Finance, ESCo Planning & Consent Programme Management Procurement Management Risk Management Value Engineering Construction Management Health and Safety Performance Monitoring Asset Management System Health Maintenance Optimisation Outage Management 21
22 Storage Financial Model
Applicable Solutions Small to Medium Demand Batteries Sodium Lithium Flywheels Medium to Large Demand Flow Batteries Compressed Air Energy Storage Liquid Air Energy Storage Pumped Hydro Storage 23
Barriers to ES Knowledge High Maintenance costs Perceived low benefit Need for cost savings Incentives not guaranteed Ownership 24
Design for Energy Storage Physical Making space Adapting designs Integrating with architecture Other factors Policy Ownership Education Public Acceptance 25
Summary Multiple Technologies Need to Bundle Revenue Streams Electricity Storage Increasing Need Many Benefits for Many Stakeholders 26
Thank you Steve Saunders Associate Director Arup t +44 (0)113 242 8498 steve.saunders@arup.com www.arup.com http://publications.arup.com/pub lications/a/a_five_minute_guide _to_electricity_storage.aspx