Post on 03-Oct-2018
Utility Scale Battery Storage – The New Electricity Revolution
by Paul Tuson, Mott MacDonald Africa (Pty) Ltd
Introduction
• Benefits of Battery Energy Storage (BES)
• Large Utility Scale BES Projects worldwide
• Storage technologies
• Forecasted BES prices
• Storage market niche and applications
• BES Environmental factors
• BES System Cost Components
• LCOE analysis
• Conclusions
2017/12/05 Mott MacDonald 2
Benefits of BES
• Load or peak shifting (both kVA (NMD) and kWh)• Reactive power (kVArh) charge reduction• Load following• Losses reduction• Congestion reduction• Reliability improvement• Capex deferral• Allowing additional load to be connected• Intermittency smoothing• Ancillary Services:
– Frequency stability– Voltage stability (inverters running in SVC mode)
• Replacement of expensive diesel generation• Off-grid hybrid schemes improvement
2017/12/05 Mott MacDonald 3
Levelised Cost of Electricity (LCOE)
• Mini-RFP
• LCOE Analysis
• Findings
2017/12/05 Mott MacDonald 15
Mini-RFP Target date delivery to site 2018
Target date commissioning 2018
Market application
Bulk energy, peak shaving and
load levellingNet Battery Bank output (less auxilliary load and other losses) (MW): MW 1 5 10 20
Net Battery Bank Energy (less auxilliary load and other losses) (MWh): MWh 6 30 60 120
Peak power discharge duration (hours) As per energy requirement
Peak power to be sustained for full discharge duration Yes
Oversizing allowed to achieve the sustained peak discharge for discharge
duration
Yes
Dicharge time at power rating Minutes to hours
Suitable storage duration Minutes to days
Modular design (upgradeable as load grows) Yes
Provision of Energy Management System (EMS) Yes
Altitude (m) 1800
Ambient temperature (deg C) -10 to 40
Connection voltages (kV) 11kV
Warranty period (years) 20
Anti-islanding protection Yes
Reactive power management capability (SVC mode) even when no active
power
Yes
Remote monitoring Yes
Outdoor installation Yes
Toxic materials or waste management system Yes
Fire and other protection systems Yes
Funding
Developer Project Finance
(Debt and Equity)
Developer TBA
Contact persons Paul Tuson
2017/12/05 Mott MacDonald 16
Mini-RFP Costs: MW 1 5 10 20
Capital Cost ($) MWh 6 30 60 120
Energy storage + chemistry
Inverter
BOS, DC rails, etc.
Supply, deliver, install, commission
Energy Management System (EMS)
Power Capital Cost ($/kW)
Energy Capital Cost ($/kWh)
O&M Cost or year or warranty cost per year ($/kW/year)
Technology (enclosed cells, flow)
Electrode chemistry
Electrolyte chemistry
Charge duration (hours)
Discharge duration (hours)
Ratio of charging duration to discharge duration
Guaranteed number of charge and discharge cycles:
Per day
Per year
20 years
Round trip efficiency (%)
Power density (W/L)
Energy density (Wh/L)
Power density (W/Kg)
Energy density (Wh/Kg)
Response time (time required to deliver power)
Depth of discharge (%)
Guaranteed degradation (% of MW)
Guaranteed degradation (% of MWh)
Major maintenance not in O&M or major component replacement over
period of project
2017/12/05 Mott MacDonald 17
LCOE Calculations
• Capital Cost– Battery system– Inverter– Control System– Balance of System (BOS)– EPC
• O&M costs (annual)• Round trip efficiency (losses on charging and discharging)• Charging Costs• Tax costs (excluded)• Maintenance outages (excluded)• Milestone replacements (assumed in the O&M costs)
2017/12/05 Mott MacDonald 18
LCOE Calculations
• Capex cost = Capex cost x 1.125
• Charging energy = BES Capacity (MW) x charge duration x 365 x 1000
• Charging cost = Charging energy x charging cost ($/kWh) x 1.125
• Charging cost = Megaflex off-peak tariff: USc5/kWh
• Operating costs assumed at 2% of capex/year
• LCOE = total cost for one year/total discharge energy in one year
2017/12/05 Mott MacDonald 19
Lazard Report LCOE – Peaker V Flow BES
• Capital LCOE - $206/MWh (46.8%)
• O&M LCOE - $72/MWh (16.4%)
• Charging LCOE - $55/MWh (12.5%)
• Tax LCOE - $32/MWh (7.3%)
• Other LCOE - $75/MWh (17%)
• Total LCOE - $441/MWh (USc44.1/kWh)
• Total LCOE (without tax) – USc33.8kWh
2017/12/05 Mott MacDonald 23
Greensmith Report – LCOE – V Flow BES
• LCOE 2016 – USc45/kWh
• LCOE 2020 – USc25/kWh
2017/12/05 Mott MacDonald 25
Comparison of LCOEs
• Diesel/HFO generation: USc40/kWh
• Battery Storage: USc23/kWh - USc45/kWh
• Coal Generation: USc10/kWh
• Hydro Generation: USc6/kWh
• Nuclear Generation: USc10/kWh
• Megaflex Winter Peak Tariff: USc20/kWh
2017/12/05 Mott MacDonald 26
Conclusions
• Certain Flow batteries (e.g. Vanadium Redox Flow) are suitable for utility scale BES due to cyclability and environmental reasons
• Vanadium Redox Flow batteries currently have a relatively poor round trip efficiency (75%)
• At current battery prices, Utility Scale BESSs can price-displace peaking Diesel/HFO generation and almost displace current Megaflex winter peak tariffs
• When stacked benefits considered, BESS even more viable• BESS systems can be installed in <12 months. Easily modularised
to match customer changing requirements and are do not impose huge capital/regulatory burdens
• Multiple small BESS systems can be distributed within the Transmission and Distribution networks to match load
• BESS systems are environmentally friendly and can support stakeholders’ “Green” objectives
2017/12/05 Mott MacDonald 28
RE Generation intermittency
Intermittent RE generation and Frequency Instability
Expensive Diesel to control frequency
Source: Mott MacDonald
2017/12/05 Mott MacDonald 33
RE Generation intermittency
BESS System Smooths RE Generation
Intermittency at Lower Cost
Source: Mott MacDonald
2017/12/05 Mott MacDonald 34
Congestion/Losses/Voltage
Congested or Overloaded Distribution System at System Peak
System LossesLow Voltage
Expensive Diesel Plant at System
Peak
Source: Mott MacDonald
2017/12/05 Mott MacDonald 35
Congestion/Losses/Voltage
BESS de-loads Distribution System at System Peak
Losses ReducedVoltage Normal
Diesel Usage Decreased at System Peak
Capex Deferral
Source: Mott MacDonald
2017/12/05 Mott MacDonald 36
BES Allows Connection of Additional Load
BESS allows additional load
Source: Mott MacDonald
2017/12/05 Mott MacDonald 37