January 2013
abstract
Responsabilité & Environnement
Gérer les énergies intermittentes électriques
Issue editor:
Gilles BELLEC
Issue 69
1. The characteristics of intermittent electricity
Do intermittent sources of electricity cause problems? Technicalities concerning solar and wind power
By Jean-Louis BAL
Président du Syndicat des énergies renouvelables
The variability of certain forms of renewable energy, mainly wind and solar (photovoltaic) power, causes quite real problems that are often underestimated and poorly understood. Variability is not something new for persons who manage electricity grids. They have to constant- ly cope with variations in the demand for electricity and with incidents affecting the means of production or transportation and distribution networks. Introducing “renewable” variables on a grid increases the need for flexibility, but does not create it. In any case, efforts should be undertaken for making grids more flexible. Let us take a look at the situation of France from now till 2020, before examining the questions that arise for most grids in the long run and then coming back to spe- cific aspects of the French situation.
Managing renewable, intermittent energy sources on electricity markets
By Mathieu BONNET
Directeur général de la Compagnie Nationale du Rhône
Given the Rhône concession and liberalization of the electricity mar- ket, the Compagnie Nationale du Rhône (CNR) has worked out an inte- grated model for managing renewable, intermittent sources of energy (water, wind, photovoltaic) that revolves around forecasting, opti- mization and market access. It is much harder — but not impossible — to manage these forms of energy than classical thermal technology. CNR’s system, which enables it to increase the value of its production and develop its storage capacity, is indispensable for harnessing these old sources of energy with new technology. This model lies at the core of the “CNR process”, next to operating and maintaining installations, and underlies the company’s future development. The latter entails aggregating other assets and anticipating possible changes owing to smart grids, distributed production and new storage possibilities.
Managing intermittent sources of electricity: The prospects opened by research
By Bernard BIGOT
Administrateur général du CEA
Beyond the difficult question of foreseeing the additional cost of plac- ing one kWh of electricity on the grid — a cost that must be kept as low as possible to improve the technology for harnessing and con- verting energy — the growing share of electricity from renewable energy sources in national consumption (initially in replacement of fossil fuels) raises questions for research. How to limit the factors that make most of these forms of energy intermittent? One solution involves developing local or centralized storage capacities that are technically and economically efficient. Another proposal has to do with introducing information technology in electricity grids and elec- tric appliances in order to reverse the currently prevailing rationale so that demand adjusts to supply, and not the reverse, in proportions that, though probably limited, are indispensable.
2. The impact on electricity grids and the adjustment of supply to demand
The interaction between nuclear and renewable sources of energy and its systemic effects in low-carbon electricity grids
By Pr. Jan Horst KEPPLER
Professeur d’économie à l’Université Paris-Dauphine, directeur scien- tifique de la Chaire European Electricity Markets (CEEM) et codirecteur du Master Energie, Finance Carbone (EFC) (jusqu’au mois de février 2012)
This presentation of the findings of Nuclear energy and renewables: System effects in low-carbon electricity systems (recently published by OECD’s Nuclear Energy Agency) analyzes the interactions between “variable renewables and dispatchable energy technologies” (mainly wind and solar power). It describes the major effects of these interac- tions on the electricity grid and systematically estimates the associat- ed costs for six OECD countries.
The impact of intermittent sources of energy on the market price of electricity
By Patrick ADIGBLI
Analyst, Product Design Department, EPEX SPOT
Parallel to liberalization of the electricity market, these past twenty years have been marked by a strong expansion of renewable energy in Europe. The increasing share of renewables in the energy mix — with a goal set by the European Commission at 20% by 2020 — has an impact on market prices. In the short run, subsidized intermittent energy may lead to lower prices or even to negative prices during cer- tain periods of the year.
How intermittent energy contributes to improving the carbon footprint assessment
By Jean-Louis BOBIN
Professeur émérite – Université Pierre et Marie Curie,
3. Industrial policy
What impact do intermittent sources of electricity have on the network for distributing electricity?
By Dominique MAILLARD
Président du directoire de RTE (Réseau de Transport d’Electricité)
Bringing electricity from renewable energy sources onto the grid is a major structural issue for the evolution of the power system in the coming years. Advances must, therefore, be made in operating grids by making them “smarter” and reinforcing coordination between grids Europe-wide. In addition, an adapted network for transporting electric- ity should be developed that is interconnected at the European level so as to benefit from “energy complementarities” in this geographic zone.
Managing the output of intermittent sources of electricity: Managers of distribution networks at the center of smart grids
By Gilles GALLÉAN
Membre du Comité exécutif d’Électricité Réseau Distribution France (ERDF), Directeur Technique
A literal revolution is under way in electricity grids owing to: the rapid decentralized production of electricity, the emergence of an active management of demand, the announcement of new means of storage, and the development of new uses, such as electric vehicles. These changes will gradually happen, differently depending on the country and region; but they will combine to form a system that, to be man- aged, will call for more intelligence, robots and electronics. At the junction between the production and consumption of electricity, dis- tribution network managers must oversee the new system’s technical complexity, limit rising costs and guarantee the quality of the services expected by clients
Managing intermittent energy for generating electricity on islands
By Bernard MAHIOU
Directeur Finances et Développement, EDF Systèmes Energétiques Insulaires
France’s “electric islands” are the overseas departments and Corsica that have small, isolated grids in “zones not interconnected” (ZNI) with the continental grid. What characterizes them is the strong growth of consumption and the quite high cost of electricity, the latter heavily subsidized through arrangements under the legal obligation to “contribute to the public service of electricity”. Renewable, intermittent forms of energy (especially photovoltaic) have grown exponentially on these islands since 2008 thanks to the backing of public policies for setting objectives, tax exemptions, and the rates for purchasing the electricity thus generated. Owing to several experiments under way, the ZNIs have become laboratories for anticipating the future difficulties that interconnected electricity grids will have to handle once the share of renewable, intermittent electricity will have risen significantly in the energy mix.
2.2. Les réseaux électriques en Europe
Development of the German network for transporting electricity: A major challenge for manager
By Olivier FEIX
Directeur Communication et Relations Publiques de 50Hertz, ges- tionnaire allemand de réseau de transport d’électricité
The catastrophe at the Japanese nuclear power plant in Fukushima has deeply altered Germany’s energy policy. The news from Japan forced the federal government to step up its efforts so as to expand more quickly the share of renewable sources in the German energy mix and, on short notice, put an end to nuclear power. This Energiewende, as the Germans call it, is a major policy priority for the government and an outstanding project that mobilizes all of German society. This turning point in energy policy has entailed rewriting several laws so as to provide a legal framework for the transition. Most stakeholders expect that important amendments will be made to the texts directly related to production facilities. What is noticeable and even surprising is the scope of the changes in laws about electricity grids, in particular about managing and developing the network for transporting electricity.
Renewable energy integration into the Spanish power system
By Miguel R. DUVISON GARCÍA
Red Eléctrica de España (REE) Madrid, Espagne
The increase in renewable energy sources in the Spanish peninsular system, along with the installation of other technologies represents a challenge due to the particularities of this type of technologies. Innovative solutions and new operation paradigms may be needed in order to cope with these challenges. Grid codes must incorporate new specifications for these technologies and demand management strategies must be incorporated in control centers in order to balance the system, maximize renewable production and maintain system security. In real time, the most significant improvements that ease integration of renewable resources are the introduction of observability and controllability, which is especially important in dealing with the problem of system balancing and the impact of renewable energy on matching generation and demand. In this regard the commissioning of a control center specifically for management of these technologies have been taken in the Spanish electrical system in order to integrate the maximum amount of renewable energy. Keywords-component; renewable energy; integration; flexibility; observability; controllability; manageable generation; system balancing; electric car; management demand; control centre; CECRE; REE.
Which EU policies for electricity grids?
By Marc GLITA
Ingénieurs des Mines
The development of alternative energy sources has encountered often unexpected political and economic difficulties: the generous rates for purchasing this electricity (set to give a boost to wind and photovoltaic power); the subsidies necessary for maintaining output during spikes in demand (which cause a sharp increase in CO2 emissions) so as to avoid sharp fluctuations on the grid; and, not to be forgotten, the development of networks for transporting electricity from places of production to places of consumption. In Germany, 4.500 km of lines are needed. The steep investments required for this have run up against opposition from public opinion with, as a consequence, the construction in ten years of only 100 km of new lines. Furthermore, reinforced interconnections between EU member states have led each country, such as Germany or Denmark, to transfer onto its neighbors the responsibility for coping with the intermittence of production that ensues from its own national decisions. After the European euro crisis, will there be an electricity crisis?
Flexing but… electric!
By Philip LOWE
Membre du cabinet du commissaire à l’Énergie à la Commission européenne
The total share of renewable energy in EU electricity should rise from 19,4% in 2010 to 34% in 2020. Changes in generating electricity — as implied by the EU’s commitments for reducing CO2 emissions and increasing the share of renewables in its electricity mix — require that grids become much more flexible than they currently are.
Distributed load shedding: A new industrial technique, born in France, is going to contribute worldwide to a fairer transition in energy
By Pierre BIVAS
Président directeur général de Voltalis S.A.
Owing to the possibility of steering demand so as to help maintain an equilibrium on the electricity grid, distributed load shedding is a new activity with worldwide outreach. It will help us save up to 15% of energy by eliminating wastage — at no cost to consumers or taxpayers. It is profitable if we take into account the savings made for the grid as a whole in terms of energy and avoided investments. Suppliers oppose it, since they seek to sell more energy at a higher price. They even pretend that they want to take up this activity in spite of years of foot-dragging on this technology and an evident conflict of interests. Nonetheless, the regulatory framework is being set up with courageous, lucid support from public authorities. This technique, created by Voltalis in Europe, promises savings for the seven million allelectric households (many of them low-income) in France. It will directly create thousands of jobs. This technological, environmental and social innovation is evidence of the turn toward a fair energy transition made by France.
3. La politique industrielle
The French wind power industry
By Alain LIGER
Ingénieur général des Mines, Conseil général de l’Économie, ministère de l’Économie et des Finances et ministère du Redressement productif
Wind power, present in France since the 1990s, produced 6.750 MW of electricity at the end of 2011. Even though recent operations and machines are of foreign origin, this does not mean that French companies are absent on this market; nor that these machines have no French-made components. The current development of offshore wind farms represents a genuine strategic opportunity for French firms, since France, besides geographical conditions favorable to such installations, has, via its parapetroleum industry, the know-how in matters related to the sea.
European industrial policy with regard to photovoltaic electricity
By Fabrice DAMBRINE
Ingénieur général des Mines, Président de la section Innovation, compétitivité et modernisation du Conseil général de l’Économie, ministère de l’Economie et des Finances et ministère du Redressement productif
The production of photovoltaic electricity has increased considerably over the last decade, especially in Europe and particularly in Germany and Italy, owing to the stimulus imparted by the advantageous rates for purchasing this electricity and by the steadily decreasing price of photovoltaic modules. This growth will continue in countries with intense sunshine and in areas that lack interconnected grids or where production is maximal during demand peaks caused by air-conditioning. Growth will also continue in the industrialized countries that want to rebalance their energy mix and break out of their heavy dependence on fossil fuels and nuclear power. In 2011, installations for generating nearly 30 GWc of solar photovoltaic power were set up around the world; and total power from this source at the end of 2011 was nearly 70 GWc, and could reach 300 GWc in 2020. This raises questions about how to develop industries for satisfying this demand.
Managing intermittence in the production and transmission of electricity: An industrialist’s view
By Jérôme PÉCRESSE
Jérôme PÉCRESSE
The growth of worldwide demand for electricity — probably 2,4% over the period from 2006 to 2030 — combined with the impact of environmental concerns on national energy policies — thus with a larger share for renewable energy sources — calls for new solutions for making the electricity system more flexible in terms of the means of production and grid management.