what wind needs is storage-chop chop. you need undulation, but no variance.
You need 60 of these a second.
Wind varies this way. Frequency of a speed is in red given by height, and output power for that speed is in blue. From 5 mph on it is useful and the red line against the blue background tells you what you get that is high quality power. Obviously from the blue MWhrs you get some below that, but it is small.
Distribution of wind speed (red) and energy (blue) for all of 2002 at the Lee Ranch facility in Colorado. The histogram shows measured data, while the curve is the Rayleigh model distribution for the same average wind speed. Energy is the Betz limit through a 100 meter diameter circle facing directly into the wind. Total energy for the year through that circle was 15.4 gigawatt-hours.
And this way..
seconds on bottom
hours of day on bottom.
And you gotta put it in the right state and the right cost environment too, that is not shaded here, but you could build a map overlay. Sort of Venn-like.
We should see more of this.
yourgreendream.com
It is not really new.
What to do when the wind don't blow you the right way.
Coping with intermittency
* As the fraction of energy produced by wind ("penetration") increases, different technical and economic factors affect the need, if there is one, for grid energy storage facilities. Large networks, connected to multiple wind plants at widely separated geographic locations, may accept a higher penetration of wind than small networks or those without storage systems or economical methods of compensating for the variability of wind. In systems with significant amounts of existing pumped storage (e.g. UK, eastern US) this proportion may be higher. Isolated, relatively small systems with only a few wind plants may only be stable and economic with a lower fraction of wind energy (e.g. Ireland).
* On most large power systems a moderate proportion of wind generation can be connected without the need for storage. For larger proportions, storage may be economically attractive or even technically necessary.
* Long-term storage of electrical energy involves substantial capital costs, space for storage facilities, and some portion of the stored power will be lost during conversion and transmission. The percentage retrievable from stored power is called the "efficiency of storage." The cost incurred to "shape" intermittent wind power for reliable delivery is about a 20% premium for most wind applications on large grids, but approaches 50% of the cost of generation when wind comprises more than 70% of the local grid's input power. See: Grid energy storage
Cement works in New South Wales, Australia. Energy-intensive process like this could utilize burst electricity from wind.
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Cement works in New South Wales, Australia. Energy-intensive process like this could utilize burst electricity from wind.
* Electricity demand is variable but generally very predictable on larger grids; errors in demand forecasting are typically no more than 2%. Because conventional powerplants can drop off the grid within a few seconds, for example due to equipment failures, in most systems the output of some coal or gas powerplants is intentionally part-loaded to follow demand and to replace rapidly lost generation. The ability to follow demand (by maintaining constant frequency) is termed "response." The ability to quickly replace lost generation, typically within timescales of 30 seconds to 30 minutes, is termed "spinning reserve." Nuclear power plants in contrast are not very flexible and are not intentionally part-loaded. A power plant that operates in a steady fashion, usually for many days continuously, is termed a "base load" plant. Generally thermal plants running as "peaking" plants will be less efficient than if they were running as base load.
* What happens in practice therefore is that as the power output from wind varies, part-loaded conventional plants, which must be there anyway to provide response (due to continuously changing demand) and reserve , adjust their output to compensate; they do this in response to small changes in the frequency (nominally 50 or 60 Hz) of the grid. In this sense wind acts like "negative" load or demand.
* The maximum proportion of wind power allowable in a power system will thus depend on many factors, including the size of the system, the attainable geographical diversity of wind, the conventional plant mix (coal, gas, nuclear) and seasonal load factors (heating in winter, air-conditioning in summer) and their statistical correlation with wind output. For most large systems the allowable penetration fraction (wind nameplate rating divided by system peak demand) is thus at least 15% without the need for any energy storage whatsoever. Note that the interconnected electrical system may be much larger than the particular country or state (e.g. Denmark, California) being considered.
* It should also be borne in mind that wind output, especially from large numbers of turbines/farms can be predicted with a fair degree of confidence many hours ahead using weather forecasts.
* The allowable penetration may of course be further increased by increasing the amount of part-loaded generation available, or by using energy storage facilities, although if purpose-built for wind energy these may significantly increase the overall cost of wind power.
* Existing European hydroelectric power plants can store enough energy to supply one month's worth of European electricity consumption. Improvement of the international grid would allow using this in the relatively short term at low cost, as a matching variable complementary source to wind power. Excess wind power could even be used to pump water up into collection basins for later use.
* Energy Demand Management or Demand-Side Management refers to the use of communication and switching devices which can release deferrable loads quickly to correct supply/demand imbalances. Incentives can be created for the use of these systems, such as favorable rates or capital cost assistance, encouraging consumers with large loads to take advantage of renewable energy by adjusting their loads to coincide with resource availability. For example, pumping water to pressurize municipal water systems is an electricity intensive application that can be performed when electricity is available.[25] Real-time variable electricity pricing can encourage all users to reduce usage when the renewable sources happen to be at low production.
* In energy schemes with a high penetration of wind energy, secondary loads, such as desalination plants and electric boilers may be encouraged because their output (water and heat) can be stored. The utilization of "burst electricity", where excess electricity is used on windy days for opportunistic purposes greatly improves the economic efficiency of wind turbine schemes. An ice storage device has been invented which allows cooling energy to be consumed during resource availability, and dispatched as air conditioning during peak hours.
* Multiple wind farms spread over a wide geographic area and gridded together produce power much more constantly.
* Electricity produced from solar energy could be a counter balance to the fluctuating supplies generated from wind. It tends to be windier at night and during cloudy or stormy weather, so there is likely to be more sunshine when there is less wind |
