Modern power grids as key element in a sustainable supply of energy

Background, central aspects of the topic

The grids for transporting and distributing electricity are central components in the supply system. At the same time, secure and powerful grids are essential elements of Germany’s infrastructure. The grid has the task of bringing energy producers and consumers together and contributing to a reliable energy supply to all consumers. In order to do this, it must be guaranteed that at any given time the same amount of electricity is fed into the system as is consumed.

Modernising the power grids

In the past few years, fulfilling these tasks has confronted enormous challenges caused by mutually reinforcing trends: the demand for electricity has increased slowly but continuously in the past decade although grid capacity has not been expanded in the same measure to keep pace. Operation of the grids is becoming increasingly demanding since liberalisation of the electricity market means that electricity customers can now freely choose their provider. This in turn means that the grid usage of many, in part heterogeneous actors must be synchronised and managed. At the same time, since the start of the so-called incentive regulation, grid operators have found themselves facing increased pressures on efficiency and costs with regard to the operation, maintenance and expansion of the grids.

A further significant factor is the increasing growth in the production of electricity from renewable sources of energy. This is a central component of German energy and climate policy. The portion of consumed energy provided by renewable sources is supposed to increase to 30% by the year 2020 and continue to grow even after that. A large portion of the growth in renewable energy is based on technologies that supply fluctuating volumes. This includes wind power but increasingly also solar power. The strong increase in fluctuating supply means that the demands placed on electricity supply and its structure are undergoing great changes. This has drastic consequences on the demands placed on the power grids. On the one hand, the fluctuating supply must be temporally matched with the demand for electricity. On the other hand, it has become necessary, for instance due to the development of powerful off-shore wind parks, to transport considerable amounts of energy over great distances to consumers.

It is to be expected that the use of innovative technologies will make a decisive contribution toward optimising grid operation (e.g. temperature monitoring in conductor cables), grid reinforcement (e.g. modern power electronics to regulate load flows) as well as updating and expanding the grid (e.g. high voltage direct current transmission, HVDC) including the use of storage technologies (e.g. compressed air reservoir and, prospectively, electrically powered vehicles).

The widespread use of information and communication technology may make the fundamental transformation of the grid infrastructure into a smart grid possible. Options in this direction exist on the supply side (virtual power plants), in the area of the grid itself and with consumers. Information and communications technology could, for example by means of modern “smart meters” in connection with new pricing structures (“real-time pricing”), enable consumers to play a significantly more active role in the future in synchronising production and consumption. This might take the form of preferentially turning on household appliances (e.g. a washing machine) when the availability of regenerative electricity is high. That this is no trivial matter is emphasized by one number. It is namely estimated that the investments needed for the modification of the grid infrastructure in Europe will amount to approximately 500 billion euros by 2030.

Current studies and pilot projects

The high significance that the relevant actors attribute to this topic is reflected in a number of comprehensively planned studies and pilot projects. These include, for example:

dena Grid Studies I and II

The central goal of the first dena grid study (project completion was in February 2005) was to develop strategies for the integration of regenerative sources of energy into the existing system of providing electricity. Concrete measures were suggested, such as the new construction of certain high voltage lines, with which a proportion of up to 20% renewable energy could be integrated into the electrical grid by 2015/2020. Based on this, the second dena grid study developed a long-term perspective for the integration of renewable energy, in particular wind energy, in the German interconnected system. The target was raised to 30% renewable energy. Members of the project group include companies and organisations in the energy industry as well as the German Federal Ministries of Economics and Technology (BMWi) and for the Environment, Nature Conservation and Nuclear Safety (BMU).

Lighthouse Project eEnergy: Energy System of the Future Based on Information and Communication Technology

This is an interdepartmental programme of the BMWi and BMU, the goal of which is to develop and test technology partnerships in pilot regions. It is supposed to promote the key technologies and business models for an “Internet of energy” until they are ready for the market. Six pilot projects are currently being sponsored.

GreenNet (Large-Scale Consortium FP7 and BMU)

GreenNet-Europe combines a number of projects that have been received support from the EU Commission in the past few years. The core consists of eleven research institutes and companies from the energy industry. GreenNet is also supported by the BMU. Its goal is to support and promote the integration of a high proportion of renewable energy sources into European power grids and electrical systems. Least-cost strategies are to be developed, from which on the basis of best-practice criteria recommendations for political action are to be derived.

DESERTEC

The goal of the DESERTEC project is to ensure the energy supply of the EU and the Near East/North African region in a rapid and economical manner by means of cooperation between these countries. The feed-in of solar thermally produced electricity from sun-rich regions into the European power grid is supposed to take place with relatively little loss via HVDC transmission. At the initiative of the non-profit organisation DESERTEC Foundation, in cooperation with the Munich Re insurance company, a new consortium was founded that wants to expedite implementation of the project.

North Sea Offshore Grid Initiative

In December, 2009, the North Sea Offshore Grid Initiative was established by a political declaration by the EU countries bordering the North Sea and Ireland. The BMWi participated for Germany. Among the goals of the North Sea off-shore alliance are a more intensive exchange of information about the goals and policies of the participating countries with regard to offshore development, a stronger coordination of the further development of the electricity infrastructure as well as the creation of a political and regulatory framework for the plans for international offshore development in the North Sea. It is planned that a memorandum of understanding will be signed at the end of 2010 that will specify the further procedure.

Aim and procedure

The objective of the technology assessment project is to point out the technological prospects and options for reconstruction and operation of the future power grid for a medium- and long-term period (2030 and beyond). The following focal points are supposed to be prepared:

• Identify pioneering technologies and forms of operating power grids by means of horizon scanning.


• Examine their potential for flexibility and for increasing capacity and efficiency in operating the power grids (both nationally and in a European network), also with regard to the increasing demands being placed on load-frequency control.


• Analyse the technical and organisational options for increasing demand flexibility.


• Consider aspects of user acceptance.


• Examine issues of data privacy.


• Estimate the need for research and development and the required periods of time (road map).


• Analyse the cost and utility.


• Examine the effects on the environment.


• Identify the appropriate instruments (regulation, financial incentives) for promoting the creation and diffusion of innovations.


• Formulate the demands on regulation that would make possible the erection of intelligent grids and the utilization of intelligent meters throughout the entire area covered (technological standards, taking their costs into consideration in regulating the charges for using the grid, etc.).