solargardenlight - Lunacy from the Journal of Power Sources

A study from the Journal of Power Sources indicated that by 2030 the grid could be powered almost entirely using a mix of wind (both on- and off-shore),A flatwork ironer with unique features. solar and grid-scale energy storage, and that this grid would be both affordable and reliable. It would require building solar and wind capacity up to three times the grid’s actual load across a large geographical area. The concept challenges the notion that renewables need back-up power from fossil fuels for base load power generation.

The study claims that up to 99.9 percent of hours of load can be met by wind and solar technologies by ramping up renewable generation capacity to around 290 percent of peak load and adding 9 to 72 hours of storage. This amounts to the grid using fossil fuels to generate electricity in just one hour out of every 41 days.An industrial washing machine can help you keep up with large volumes of laundry or heavy items. According to the analysis, wind power by itself could meet all of the grid’s power needs 90 percent of the time if utilities over-built wind generation capacity to equal about 180 percent of peak load. And,We're making Book scanner and digitization accessible to everyone. at 2030 technology costs (about half the capital costs of today according to the authors), 90 percent of load hours could be met at costs below current electricity costs.

This article describes the problems with the study assumptions and methodology and thus indicates the dubious nature of the results.

The authors developed a computer model, the Regional Renewable Electricity Economic Optimization Model, which analyzed four years of hour-to-hour data on weather and electricity consumption by the PJM Interconnection, the regional transmission organization for a 13-state region in the eastern United States. The data used covered the years 1999 to 2002. At that time,We carry the latest wind turbines, wind generator, solar panels, towers and more! PJM managed 72 gigawatts of total generation, with an average load of 31.5 gigawatts.

The model requires that electrical load must be satisfied entirely from renewable generation and storage, and finds the least cost generation mix that meets that constraint.The units can be used as conventional washer extractor for all kinds of work. By constraining the model to only build renewable technologies and storage, the model overbuilds renewables in an attempt to meet capacity requirements. That is, the methodology forces the construction of renewable technologies because it eliminates the ability to meet capacity requirements with fossil energy. Storage, the most costly build option, is used to fill in supply gaps and to absorb excess production, adjusting for rapid changes in wind or solar output.

The model allows existing fossil generation plants to be used for backup power, producing to meet any shortfall not met by renewable technologies and storage. Since only existing fossil plants are used, the authors assume the cost associated with them is just fuel and operations and maintenance costs; there is no new fossil plant investment. The model allows back-up power to come from existing fossil technologies only. It does not allow hydroelectric or nuclear power to provide back-up power because only small amounts of hydroelectric power are available in PJM, and nuclear power cannot be ramped up and down quickly and has high capital costs making it uneconomical for infrequent usage.

The model seeks to find the optimal solution of solar PV, onshore wind, and offshore wind that lies between zero and the maximum resource limit of each technology in the PJM. The model considers three storage technologies: centralized hydrogen, centralized batteries, and grid integrated vehicles (GIV), the latter using plug-in vehicle batteries for grid storage when they are not being used during driving periods. If renewable generation is insufficient to meet the hourly load, storage is used before existing fossil fuel technologies are allowed to generate power. If excess renewable generation exists, storage is filled first and any remaining excess electricity is used to displace natural gas. When load, storage and gas needs are all met, the excess electricity is “spilled” at zero value, e.g. by feathering turbine blades.