Simultaneous Imbalance Reduction and Peak Shaving using a Field Operational Virtual Power Plant with Pumps

The Dutch electricity infrastructure is challenged by the deployment of large numbers of heat pumps in newly-built domestic residences. An example is the apartment complex of Couperus in The Hague where 300 apartments are heated by individual heat pumps. This building was operated as a Virtual Power Plant for ten months. Using the PowerMatcher as a coordination mechanism, the VPP balanced a near-by wind farm providing a peak-shaving service to the local distribution station. Flexibility was provided by shifting the operation of the heat pumps in time, which is dependent on a certain bandwidth in the indoor temperature in the households. In this way up to 21% of the power drawn by the heat pumps was made flexible without infringing user comfort. Using this flexibility, 94% of the wind farm imbalance was reduced. Further, the system successfully performed peak-load reduction at the LV-to-MV substation simultaneously to the VPP operation. During the test indoor temperatures and the status of the heat pumps were recorded to secure user comfort. The Couperus project is one of a few smart grid demonstrators that did not include friendly users only, as all occupants in the apartment building were included in the demo. Therefore, the operational temperature bandwidth was set to a conservative value of 0.4 °C to avoid any loss of comfort. As a result, no complaints of the inhabitants with respect to the temperature were reported

The interaction of hydrogen and carbon monoxide with oxygen on Cu(110)-Fe surfaces

The interaction of hydrogen and carbon monoxide with oxygen adsorbed on Cu(110)-Fe surfaces has been studied with ellipsometry, Auger electron spectroscopy and low energy electron diffraction. With carbon monoxide copper can be reduced completely and Fe0.95O partially. With a model which is only an extension of the scheme for the reduction of pure Cu(110) by CO, the reduction of Cu(110)-Fe can be simulated. The lateral orientation of Fe0.95O with respect to the copper matrix changes during repetitive oxidation-reduction cycles. At 725 K oxygen deficient iron oxide segregates to the surface. With hydrogen all oxygen can be removed

The interaction of hydrogen and carbon monoxide with oxygen on Cu(110)-Fe surfaces

The interaction of hydrogen and carbon monoxide with oxygen adsorbed on Cu(110)-Fe surfaces has been studied with ellipsometry, Auger electron spectroscopy and low energy electron diffraction. With carbon monoxide copper can be reduced completely and Fe0.95O partially. With a model which is only an extension of the scheme for the reduction of pure Cu(110) by CO, the reduction of Cu(110)-Fe can be simulated. The lateral orientation of Fe0.95O with respect to the copper matrix changes during repetitive oxidation-reduction cycles. At 725 K oxygen deficient iron oxide segregates to the surface. With hydrogen all oxygen can be removed

Multi-agent control for integrated heat and electricity management in residential districts

For the built environment it is envisaged that in the next decades the total annual energy demand, both thermal and electric, could be covered by renewable sources generated within the built environment. More and more thermoelectric elements, such as heat pumps and thermal storage, will enable conversion from heat to electricity and vice versa. Control in this environment therefore requires an integral management of both heat network and the electricity network. In this paper we present of a market-based multi-commodity algorithm for integrated coordination of electricity and heat flows at the residential district level. The algorithm is an enhancement of the PowerMatcher concept for electricity alone and inherits its advantages such as scalability and user autonomy. Some examples are given to demonstrate the usability of algorithm in residential areas to unleash a large flexibility potential of heat and electricity flows in support of the integration of renewable energy

Preparation of Cu(110)-Fe alloys and their reactivity towards oxygen

Cu(110)-Fe alloys are prepared by thermal decomposition of Fe(CO)5 at 600 K. Iron facets grow under an inclination angle of 35.2° with the surface exposing a (110) plane. The majority of iron is distributed below the surface layer and there is hardly any enrichment of copper at the surface layer. Oxygen adsorption is not noticably accelerated compared to that on Cu(110). At temperatures below 400 K even a decrease in sticking coefficient is noticed. The total oxygen uptake increases with temperature and iron content

Intelligent energy management using powermatcher: Recent results from field deployments and simulation studies

Response of demand, distributed generation and electricity storage (e.g. vehicle to grid) will be crucial for power systems management in the future smart electricity grid. In this paper, we describe recent results using PowerMatcher a smart grid technology that integrates demand and supply flexibility in the operation of the electricity system through the use of dynamic pricing. Over the last few years, this technology has been researched and developed into a market-ready system, and has been used in a number of successful field deployments. Recent field experiences and simulation studies show the potential of the technology for network operations (e.g. congestion management and black-start support), for market operations (e.g. virtual power plant operations), and integration of large-scale wind power generation. The scalability of the technology, i.e. the ability to perform well under mass-application circumstances, has been demonstrated in a targeted field experiment. This paper gives an overview of the results of two field deployments and three large simulation studies. In these deployments and simulations, demand and supply response from real and simulated electrical vehicles, household appliances and heating systems (heat pumps and micro co-generation) has been successfully coordinated to reach specific smart grid goals

Design of an agent architecture based on the powermatcher approach for coordination of heating and cooling in buildings and domestic dwellings

A lot of simultaneous processes do occur in a building. With the increase of the number of devices for heating and cooling of the building, there is a higher risk of one device counteracting the other. This leads to unnecessary loss of energy. It is becoming harder for conventional comfort control systems to satisfy the objective: „provide thermal comfort at the lowest energy use¿. Multi Agent systems for climate control can offer a number of advantages in this field because of their bottom-up modelling principle starting from the low-level primary process, in this case comfort control. The aim of our research in the Flexergy project is to design a Multi agent climate control system for buildings and domestic dwellings as well. In the process of obtaining this, an intermediate goal as an objective for a study was spontaneously formulated. During the operation of a central control system for a representative office building in the Netherlands, it was observed that, due to high insulation, solar irradiance and internal heat sources, the net demand for cooling over a year is higher than for heating. As a heat pump connected to an aquifer was responsible for delivering the cooling power it was also observed that the temperature of the aquifer increased. This decreases the availability of cooling power for the building in near future. The question was raised how a multi agent could help to retain the energy balance of the aquifer over a year. It was suggested that two technical possibilities to retain this balance could be exploited: first to cool the building by outdoor air during the morning hours by an air conditioning unit and second to load cold during the night with a bypass preventing warm air from entering the building. This study describes the details of a design of a simplified Multi agent climate control aimed at retaining the energy balance of the heat pump connected to an aquifer, exploiting the ability of the PowerMatcher to trade two or more commodities through the use of the above mentioned methods [2]