There economic and technical problems with using a lot of solar and wind.
Solar is subsidized with net metering where the utility is forced to store the excess solar power.
Hawaii has reached the point with solar energy (40%) where they are burning out their grid.
Wind causes severe frequency fluctuations both above and below 60 Hz.
Power Transients reduce reliability.
Non-dispatchability requires standby generation
Low capacity factor hurts payback (EROI).
Geographic non-optimal limitations.
Resonance between power line compensators and rotating machinery.
Sudden gusting behavior for wind, and cloud cover for solar both introduce serious transient behavior in power supply. Backup Power supplies that can compensate for this are inefficient in their use of fuel (Single cycle gas turbines vs. combined cycle) Regardless, operators must meet their obligations to provide high quality CONSISTENT power.
System Operators are SERIOUSLY penalized for violations of contractual power quality. Grid operators are heavily fined, sometimes millions of dollars per year for failure to appropriately regulate power. Brownouts/Blackouts are serious cost issues for large industry. Reliable power is the goal in utility industry. They typically operate at 99.5% or more (less than half a day per year)
A system is reliable if its components are individually reliable and connected in a fail safe configuration. Components are individually reliable if they have an appropriate MTTF remains constant across all modes of operation. Variability is more difficult to plan for appropriately and penalizes the cost structures built into utility financial models.
“There is not a single transmission expansion project in this country that is not currently being challenged by land owners.” – Pat Hoffman
“From Florida to California distribution feeders are being overloaded due to home generation of solar energy” – Pat Hoffman
“Many long lines in the western interconnect are currently being series compensated” – Pat Hoffman
(Pat Hoffman is Assistant Secretary of Department of Energy Office of Electricity Delivery and Energy Reliability.)
IEEE Subsynchronous Resononance Working Group, “Second Benchmark Model for Computer Simulation of Subsynchronous Resonance,” IEEE Transactions on Power Apparatus and Systems, Col. PAS-104, No. 5, May 1985.
R.C. Dugan, M.F. McGranaghan, S. Santoso, H.W. Beaty, “Electrical Power Systems Quality, 2nd Ed.” McGraw-Hill, 2003.
J.D. Glover, M.S. Sarma, T.J. Overbye, “Power System: Analysis & Design, 5th Ed.” Cengage Learning, 2012.
A.M. Dodson, R. McCann, “A Modular Multilevel Converter for Series Compensation of an EHV Transmission Line with Battery Energy Storage,” Power Electronics Conference of Illinois, PECI Feb. 2013
M.G. Molina, P.E. Mercado, “Comparative evaluation of performance of a STATCOM and SSSC both integrated with SMES for controlling the power system frequency,” IEEE/PES Transmission & Distribution Conference & Exposition, 2004 Latin America.
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M. El-Moursi, B. Bak-Jensen, M. Abdel-Rahman, “Novel STATCOM Controller for Mitigating SSR and Damping Power System Oscillations in a Series Compensated Wind Park,” IEEE Transactions on Power Electronics, vol.25, no.2, pp. 429-441, Feb. 2010.
Fig. 1 — Frauhofer Institute
Fig. 2, 3 – D. Rastler. Electricity Energy Storage Technology Options: A White Paper Primer on Applications, Costs, and Benefits. Electric Power Research Institute. 2010.
Fig. 4 – IEEE P1726™/D10 Draft Guide for the Specification of Fixed Series Capacitor Banks for Transmission System Applications. IEEE. 2010
Andrew Dodson – Windfarms are Resonating Across the Grid
On our return trip from ANL (Argonne National Lab) Andrew Dodson was interviewed by Scott Medwid and Rick Maltese on the subject of grid stability, and the impact of “green energy”.
Andrew Dodson ( 1:00 )- “Windfarms in Oklahoma are now resonating with places like Dallas. You have resonances occur down these long transmission lines which are damaging major generation equipment in large cities in America.”
When you put solar on your roof, you are stealing from your neighbors. You are saying pay me to use my solar panels and give me energy whenever I ask for it. The money only flows one way.
The current grid is designed for unidirectional flow. All the protection devices are set for unidirectional flow.
Solar should have an all DC grid.