|
|
|
Research & Development
Dielectric heating, new high voltage lines, Flexible office walls, KEMA materials knowledge bank
|
|
|
Research & Development
Customers in the energy industry today attach great value to short-term solutions and applications. The Power Generation Technical Service Agreement (TSA) offers these types of solutions and applications in the form of a portfolio of a number of future options, while also taking the individual positions and strategies of the co-funders fully into account.
The TSA is based in part on the trends and challenges of the privatized energy market, on the new and emerging government policy on energy and on the latest technical developments. TSA is a contract on an individual basis, with additional advantages in the case of consortium agreements, with well-developed knowledge and product transfer and an open and professional monitoring and management structure.
The sponsors of TSA have access to all existing products that have been developed in the past ten years, the Consultancy Help Desk, Strategic Scouting & Support topics and the results of the Environmental Regulation project package. Individual sponsors are also offered the opportunity to sign up for a wide selection of projects in three main areas:- new technology / new construction
- operational support
- preservation of operating units.
The Industrial Plastics team of KEMA Power Generation and Sustainables is fully integrated into the TSA program. Each TSA sponsor is welcome to come and get detailed information about our team’s extensive fields of expertise and related topics and to benefit from it.
|
|
|
Joint industrial projects
An example of a project which KEMA in co-operation with industrial partners has executed is the development of new high-voltage cables.
Development of new high-voltage cables
Demand for electric power will continue to increase in the future. The capacity of the present high-voltage cables (the electric power cables used in high-voltage towers) is insufficient to meet this demand.
In this framework, a project was started in 1999, aiming to develop fiber-reinforced aluminum for application in a new type of electric power cable.
The present conductor contains a steel core, which has a high expansion coefficient due to temperature rises. This means the conductor can transmit only a limited amount of power, because the cables might start sagging excessively and fail to meet the specified requirements.
The new conductor will have an EFRA (Endless Fiber Reinforced Aluminum) core and a sheath of aluminum wires. This conductor will be able to transmit more power because the carbon fibers in the aluminum cause the material’s expansion to be far less at equal power transmission, so that the conductor will be less prone to sagging.
The COPREM (COntinuous PRocessing of Endless fiber-reinforced Metal wires) project was carried out by a European consortium of cable manufacturers, power distribution companies, universities and other research institutes, including KEMA. In the first stage, research focused on fiber types that might qualify for aluminum reinforcement. Carbon fibers appear to have more advantages and better properties than for instance ceramic fibers. Carbon fibers are cheap and have an extremely low expansion coefficient, while ceramic fibers are generally a lot more brittle by nature and therefore more susceptible to damage, which will restrict the anticipated service life.
The next step in this project is to produce such fibers of the greatest possible length for economical application in high-voltage cables. There will also be an emphasis on how environmental aspects can be considered in the design stage and what is the new conductor’s potential for recycling of the materials used.
|
|
|
Dielectric heating
With conventional heating, in which heat is usually supplied from outside, heating takes place relatively slowly and hardly ever homogeneously. This is due to the fact that most materials or objects to be heated do not conduct the heat in ideal fashion. Moreover, particularly drying processes can be very time-consuming, since the thermal resistance of the material to be dried increases as it gets drier. Also, losses are inevitable in such heating processes, because not only the material itself but also its environment is heated.
For most processes requiring heating, heat supplied from outside is sufficient. However, for other processes there may be heating methods offering a better solution. One of these other methods is dielectric heating. This technology generates heat inside the material itself and the material’s thermal resistance no longer matters; hardly any heat transmission into the material takes place. Using dielectric heating, it is possible to heat materials in a short period of time and without local temperatures increasing excessively.
The application of dielectric techniques offers major economic benefits in some cases, despite the fact that the technology is relatively expensive. Efficiency of the entire production process can be increased significantly because a great deal of time can be saved in heating and drying processes. Also, constant quality can be guaranteed because the heating system can be accurately regulated and heating takes place very homogeneously. These are the reasons why this technology is used in industry.
The main differences between conventional heating, for example by means of hot air, and dielectric heating are given in the table below.
Conventional heating |
Dielectric heating |
heat from outside |
heat generated inside material |
heating hardly ever homogeneous |
homogeneous heating |
poor heat conduction |
heat conduction irrelevant |
time-consuming drying processes |
rapid drying processes |
heat loss |
little heat loss |
sizeable installation |
compact installation, taking up little space |
For more information, please contact us.
|
|
|
|
|
|
|
|
