CAPACITY RENEWABLE ENERGIES The Market Strategy Board White Paper - - PowerPoint PPT Presentation

GRID INTEGRATION OF LARGE- CAPACITY RENEWABLE ENERGIES

The Market Strategy Board White Paper

Presentation by: Adam L. Reed, J.D., Research Associate Renewable and Sustainable Energy Institute (RASEI)

Boulder Workshop – 12-15 Mar. 2012

MSB SWG 4.2 Project Team Members

Hiroyuki Abe, NGK (JP) Gabriel Barta, IEC Jianbin Fan, SGCC (CN) Juan Hu, SGCC (CN) Peter Lanctot, IEC Caihao Liang, SGCC (CN) Enno Liess, IEC Puneet Pasrich, CU-Boulder Adam Reed, RASEI Toshiyuki Sawa, Hitachi (JP) Hong Shen, SGCC (CN) Giordano Torri, SpA (IT) Yoshimitsu Umahashi, TEPCO (JP) Zhankui Zhang, SGCC (CN)

Non-PT Workshop Experts

George Arnold, NIST (US) Kara Clark, NREL (US) Paul Denholm, NREL (US) Steve Hauser, NREL (US) David Hurlbut, NREL (US) Lawrence Jones, Alstom Grid David Kline, NREL (US) Mike Knotek, RASEI (US) Ernst Scholtz, ABB (CH) William Wallace, NREL (US) Philip Weiser, CU-Law (US)

The White Paper(s) in Context

“The present White Paper is the third in a series whose purpose is to ensure that the IEC can continue to contribute with its standards and conformity assessment services to the solution of global problems in electro-technology.”

• - Executive Summary

Electricity Systems are Changing

• Increasing interconnectedness
• f systems and equipment
• Increasing complexity and

quantities of data

• Technical challenges are

arising that do not have purely “device-level” solutions

• What is the role of IEC

standards and assessments in contributing to these “systems-level” problems, and their many potential solutions?

Introduction: Large Capacity RE and EES

“Integration of RE is a poly-nodal problem involving multiple decision-makers at a variety of spatial and temporal scales and widely varying degrees of coordination. These decision- makers include … operators of renewable energy and energy storage resources, grid operators, energy market operators, and transmission planning bodies. As such, grid integration is not performed by any one entity in the power system, but instead involves the actions of a variety of entities, some highly coordinated and others discrete. The burgeoning development of smart grids adds still more tools, options, and players to the mix. Many of these actors engage with various technology standards, practices, procedures, and policies for the operation of individual generators, renewable energy clusters, substations, and the broader electrical energy system.”

• - Section 1

In other words…

• “RE integration” is not

just about controlling RE itself—though that is

• ne potential solution.
• Rather, RE integration

may involve changes to the operation of the entire power system.

• Sec. 2 – RE Generation: present,

future, and integration challenges

• Drivers of RE development:

– Decarbonization – Energy Security – Expanding Energy Access

• Sec. 2 – Wind Energy Projections

Wind Energy Generation through 2035 by Region/Country

100 200 300 400 500 600 700 800 900 US OECD Europe Japan Russia China India Middle East Africa Latin America Brazil TWh Country /Region 1990 2009 2015 2020 2025 2030 2035

• Sec. 2 – Solar Energy Projections

Solar PV Energy Generation through 2035 by Region/Country

20 40 60 80 100 120 140 160 180 US OECD Europe Japan Russia China India Middle East Africa Latin America Brazil TWh Country/ Region 1990 2009 2015 2020 2025 2030 2035

• Sec. 2 – RE Grid Integration Challenges
• Wind and Solar present 3 primary challenges to

the grid (and at different time-scales!):

– Variability in generation output (seconds-to-hours) – Uncertainty in future availability predictions (hours-to- days) – Locationally-dependent resources may be far from load-centers, and require new transmission or upgrading of existing transmission (years)

• Sec. 3 – State of the Art
• Overview of wind, solar tech: basics, types,

characteristics

• Transmission tech by region
• VSC-HVDC advantages for RE discussed

• Sec. 3 – Forecasting State of the Art
• Short term most common, uses physical and statistical methods
• Report has detailed table of short-term forecast programs used by

different wind plants.

• Forecast error is 10-20% of installed capacity for 36 hour horizon.

Spatial aggregation greatly increases accuracy, but longer horizons decrease accuracy.

Numerical Weather Prediction (NWP)

Forecast Program

Power Output Forecast

• Sec. 3 – System Operational Practices
• Extremely wide variance b/w countries and

regions due to:

– RE generation development level – Conventional generation fleet – Grid structure – Market and institutional environments

• Report contrasts China, Denmark, Germany,

Japan, Spain, and several U.S regions.

• Sec. 4 – Future: Technical Solutions
• System “Flexibility” from a variety of sources

– Grid-friendly RE generation – Conventional generation flexibility – Demand response – Energy storage can act as generation or load – Operations enhancement within and between balancing areas, including consolidation – Transmission expansion

Variability & Uncertainty System Flexibility

• Conven. gener. outages

Grid faults RE output fluctuation Load variation Grid-friendly RE gener.

• Conven. gener. flexibility

Demand response EES

• Sec. 4 – “Grid-friendly” RE
• Volt/VAR control/regulation through built-in

capability, switched capacitor banks, SVC, STATCOM, etc.

• Fault ride-through capability
• Active power control, ramping, and curtailment

through active-stall, pitch control, discrete tripping of units

• Primary frequency regulation through pitch

regulation

• Inertial response
• Short circuit current control
• Improved generation modeling tools

• Sec. 4 – Centralized Control of RE Plant

Clusters

• RE plants may be clustered around central control

points, and should be operated in a coordinated fashion to prevent conflicts between plant-level voltage and reactive power controllers.

750kV Anxi Substation 750kV Jiuquan Substation #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 200MW 200MW 200MW 200MW 200MW 200MW 200MW 200MW 200MW 200MW 200MW 200MW 300MW 200MW 200MW 200MW 280km 330kV Substation 330kV line 750kV line Wind power plant 200MW 35kV line

• Sec. 4 – Improved Conventional

Generation Flexibility

• Currently the major source of system flexibility: hydro, gas,

coal, nuclear (in order).

• Generation-level questions remains:

– How does flexible use of thermal generators affect performance? – What might that mean for operational practices and incentive design?

• System-level questions: How can we measure a power

system’s “flexibility” in a universal fashion?

– NERC Integration of Variable Generation Task Force (IVGTF) – IEA Grid Integration of Variable Renewables Project (GIVAR)

• Sec. 4 – System Generation Planning
• “Simply having a specified number of megawatts of

capacity may not be adequate for system security if that capacity is not flexible enough to respond to system variability. … In order to consider flexibility requirements, a new paradigm of generation planning is needed.”

• Planners in high-RE systems will need to examine

adequacy of both generation capacity AND generation flexibility

Capacity Adequacy Assessment System Flexibility Assessment Production Cost Simulaiton Generation Portfolio If portfolio is unreliable in operation

• Sec. 4 – Transmission Expansion
• Exploits geographic diversity of RE generation to reduce

variability and uncertainty.

• Supports interconnection between balancing areas.
• A variety of technologies and applications reviewed:

UHVAC, FACTS, UHVDC, VSC-HVDC, MTDC, DC-grids

• Developments in probabilistic transmission planning

explored.

Initial 7 alternatives 5 alternatives 3 alternatives The best alternative Environmental, societal, and political assessment Deterministic technical analysis, including N-1 principal Probabilistic reliability evaluation Probabilistic economic analysis

• Sec. 4 – Operations Enhancement

Planning Scheduling Dispatch Control Real Time Futuristic What: Generation and transmission planning Who: System planners Time Frame: Years into future What: Unit Commitment, Maintenance Scheduling, etc. Who: Operational planners Time Frame: Hours to Days, Seasonal, Annual What: Economic Dispatch, Contingency Analysis, etc. Who: System operators Time Frame: Minutes to Hours What: Automatic frequency/voltage control, relay protection, load shedding, etc. Who: Automatic equipments and control systems Time Frame: Seconds to Minutes Operation

• More accurate RE power forecasts
• Enhancement of Operations Tools and Practices
• How to bring these enhancements into the control room effectively?

• Sec. 4 – Demand Response
• DR Functions to aid RE integration:

– Load Shifting – Demand-side Balancing Services

• DR Practices:

– Dispatchable Programs / Load Management – Reactive Programs (wholesale and retail)

• DR Goals:

– Improve reliability – Improve efficiency – Improve flexibility

• Sec. 5 – Large Capacity Electric Energy

Storage for Supporting RE Integration

• Harmonized with EES White Paper
• Re-visits grid-friendly RE generation, conventional

generation flexibility, and demand response from Sec. 4 with an emphasis on energy storage technologies and applications, including case-studies.

– Grid-side roles of EES: Time-shifting/arbitrage/load- leveling, seasonal shifting, load-following/ramping, power quality and stability, operating reserves, efficient transmission network use, isolated grid support, and black- start capability. – Generation–side roles of EES: Time-shifting, output smoothing, transmission utilization efficiency – Demand-side roles of EES: Focus on electric vehicles

• Sec. 5 – Technology Needs of EES for

RE Integration

• “…optimization of storage placement and use

within the context of the power system as a whole, both today and into the future.”

– Existing tools for storage are generally facility- specific, and presume that storage has already been installed. – A need for tools that can help us know where to place EES for optimal grid usage.

• Sec. 5 – EES Planning and Decision Tool

Concepts

• An EES planning and decision tool for utilities and

facility developers might consider the following factors, both at present and in future scenarios:

– Amounts and net variability of RE generation on the grid; – Interconnectivity of the grid to other grids, and balancing capabilities between them; – Conventional backup capacity available and desirable; – Demand-side management applications and capabilities; – System costs or market prices for operating reserves, power quality services, and balancing energy; – Time-shifting/arbitrage potential in relevant energy markets; and – Technological capabilities and flexibility of various EES technologies.

Conclusion

• Sec. 6 (standards needs) and Sec. 7

(recommendations) covered by Dr. Fan.

• Thank you for your time and attention!