Managing Volatility – Integrating Renewables into the Energy System
Figure 3: Increase in Electricity Imports After Shutdown of Eight Nuclear Reactors in Germany GWh
Moratorium comes into force 200
100 150
50 0
-50 -100 -150 -200
-250 Export (GWh)
Import (GWh) Saldo (GWh)
Source: European Network of Transmission System Operators for Electricity.
quickly available back-up capacity with a high load gradient. Due to their low capacity, of mostly 50–100 MW, they can be relatively easily used in an increasingly decentralised generation and distribution system. They can also be used to support the grid at critical demand points. Moreover, they have lower investment costs and therefore may be more acceptable to society than, for example, large pumped-storage plants.
Option 4 – Electricity Imports
Historically, Germany has been a net exporter of electricity. The existing capacities allowed stable security of supply and a net export. The increase in renewable capacities leads to even more exports. However, since Germany shut down eight of its nuclear power plants in spring 2011, it has been importing electricity from France and the Czech Republic. The imports have amounted up to 3,000 and 2,000 MW, respectively (see Figure 3).
Germany will, at least in the short term, be dependent on electricity imports. Even in the long run, the energy concept of the German government stipulates a share of almost 10 % electricity imports until 2030 and almost 30 % until 2050. This has also to be seen in a European context, as the other European countries also plan on significant electricity imports.
Option 5 – Demand-side Management
The last option considers the demand side. The principle of so-called demand-side management (DSM) is to encourage the consumer to use less electricity during peak hours. The consumer should shift the times of electricity use to off-peak times such as night-time, weekends and times when plenty of renewable energy is produced. The energy system would benefit from the corresponding smoothing of the load curve because a
1.
Directive 2009/28/EC of the European Parliament and of the Council of 23 April 2009 on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/EC and 2003/30/EC, Official Journal of the European Union, 2009. Available at:
http://eur-lex.europa.eu/LexUriServ/ LexUriServ.do?uri=OJ:L:2009:140:0016:0062:en:PDF (accessed 21 February 2012).
reduced peak demand avoids the operation of expensive peak-load power plants. Also, the consumer would benefit from the cost advantages.
One of the words currently most used in the discussion surrounding DSM is perhaps ‘smart’. A smart grid is an electricity network that can intelligently integrate the actions of all users connected to it in order to efficiently deliver electricity supplies. With a smart grid, not only the consumer but also the grid operator has access to the consumer units and can regulate their consumption depending on the load level of the energy system (peak or off-peak). It will unavoidably lead to temporary shutdowns of individual consumers, such as industrial enterprises, for example.
To realise the vision of a smart grid, customer involvement in grid control has to be increased. To make this possible, information and communication technology is needed to connect to the devices inside the house. Thus a wholly new market of home appliances arises.
The European Commission recently launched an ambitious Energy Infrastructure Package4
of a smart grid. Conclusions
Energy transition means more than just extending renewable capacities. It means the rebuild of the energy system in total. Regardless of what the energy transition will look like, it is a fact that it will involve a combination of, at least, the infrastructure measures outlined above. There is no all-in-one solution. All stakeholders must be aware that the upcoming transition period will be a very tough time for society as a whole and will require a lot of effort until all grid and integration measures are implemented. n
2. AG Energiebilanzen. Available at:
www.ag-energiebilanzen. de/componenten/
download.php?filedata=1326461230.pdf&fi lename=BRD_Stromerzeugung1990-2011%2020Dez2011. pdff&mimetype=application/pdf (accessed 21 February 2012).
3.
Federal Ministry for Economics and Technology and Federal Ministry of the Environment, Nature Conservation and Nuclear Safety, Energy Concept for an Environmentally Sound, Reliable and Affordable Energy Supply, 28 September 2010.
Available at:
www.bmwi.de/English/Navigation/Service/ publications,did=
367764.html (accessed 21 February 2012).
4.
European Commission, COM (2011) 658 final, Proposal for a regulation of the European Parliament and of the Council on guidelines for trans-European energy infrastructure and repealing Decision No 1364/2006/EC, 2011. Available at:
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri= COM:2011:0658:FIN:EN:HTML (accessed 21 February 2012).
that promises to deliver the hardware aspects
14
MODERN ENERGY REVIEW – VOLUME 4 ISSUE 1
01/03/11 03/03/11 05/03/11 07/03/11 09/03/11 11/03/11 13/03/11 15/03/11 17/03/11 19/03/11 21/03/11 23/03/11 25/03/11 27/03/11 29/03/11 31/03/11 02/04/11 04/04/11 06/04/11 08/04/11 10/04/11 12/04/11 14/04/11 16/04/11 18/04/11 20/04/11 22/04/11 24/04/11 26/04/11
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84