Energy demand management
Load control or English and Demand -Side Management ( DSM short ) refers to the control of the demand for network services for customers in industrial, commercial and private households. They relate to the energy consumption as well as on the water consumption and the use of transport infrastructure in cities with cars. Due to the demand-side management, it usually comes in a reduction in demand, without having to increase the offer (for example, by increasing the production of electricity or water).
As incentives for influencing serve frequent financial incentives such as special tariffs which, for example, a low-load control is possible. In addition, however numerous other measures are possible (eg, public relations campaigns, investments in the networks to eliminate power losses or even use prohibitions). First, the demand-side management was developed in the energy industry.
In case of bottlenecks in electricity generation ( eg if a large power plant ) or high demand (peak load during the lunch time) or disruption of network operations and resulting in a lower frequency can by remote control - in the low voltage network usually by ripple control system - single large or many small electricity -consuming equipment to be switched off and on again.
This is however only for devices and machines that can be turned off for a certain time without the user needing to be asked. In such cases, previously regulated by contract, how long and what electrically powered equipment must be switched off. The customer receives in such cases a discount on its general electricity tariff. Also, no equipment should be switched off, which are important for safety and for the consumer ( life- ) (eg alarm systems, lighting in dark corridors and rooms, computer systems).
Load control is operated for many years by the Stadtwerke Saarbrücken. Here, the freezers and refrigerators are turned off in supermarkets for a certain time. The thermostats are pre- set so that they cool or freeze food at a slightly lower temperature. Is then separated from the electric utility to remotely control the cooling unit from the mains, so they can stay off approximately 1 to 2 hours before they need to be switched on again in order to protect the food from thawing.
In many cities (eg Frankfurt, Singapore, Windhoek ) succeeded by measures of demand-side management, disconnect the water consumption from economic and population growth, so that it becomes a zero growth or even a decline consumption came from.
Due to the increasing global warming, but also by demographic change is the future in many regions of the world in water demand influences are necessary because of a seasonal or prolonged water shortages. Water utilities have already dealt extensively in recent years with the topic.
Due to the increase of the fluctuating power generation from photovoltaic and wind turbines will, among other measures, the load control get more and more important. Mechanisms are being tested in the UK and the U.S., where household appliances such as refrigerators, but also dryers and electric boilers delayed depending on the mains frequency or prematurely on and off. Thus, they are involved in the primary control. A prominent field trial of the Pacific Northwest National Laboratory tested in the U.S. state of Washington, 200 devices the so-called Grid Friendly Appliance Controller. Another field test in the UK led the company RLtec with the appliance manufacturer Indesit and the energy supplier npower through.
To increase global sustainable development, the International Energy Agency IEA carries out a DSM research program in cooperation with 15 countries, including Switzerland, Austria and Italy. Positive impact on the reliability and security of power systems, on the emissions of CO2 and pollutants, as well as system cost and price volatility are to be achieved with a kind of "toolbox" for governments and energy companies.
The Asked by DSM measures available reserve capacity in the energy sector can in principle also acted as minute reserve or on the intraday spot market of the European Energy Exchange. The selective influence consumer overload is planned in contrast to the above case, the provision of primary control power. Thus, for example, the start of dishwashers are temporally delayed or advanced, whereby each positive or negative reserve power can be provided. It should be noted that the activation of reserve power requires a further call on the day with the opposite sign, as summed over the day total load remains unchanged by time load shifts.