Answer by Researcher answerfinder on Wed 11 Nov 2009 - 10:44 am UTC:

Dear Miro,

And you thought this was going to be straightforward.

Since 1998 the generation and supply of electricity in the Netherlands has
undergone many changes with the aim of creating an open energy market. This
also enables the consumer to make their choice of which energy supplier
they wish to use.

The Netherlands national grid is operated by TenneT B.V., the company is
responsible for the main highways of the electricity network (1). This
network also connects the Dutch grid to the national grids of neighbouring
countries. So it is possible that electricity used in Rotterdam came from
Germany or Norway. At below a certain voltage level, the grid is then
controlled by regional grid administrators. In the case of Rotterdam, it is
Stedin B.V.(2)(3)
 
Since July 1, 2004 a Rotterdam consumer (both business and domestic) has
the opportunity to choose their electricity supplier. They cannot change
the network administrator. Not all the supplying companies produce all this
power themselves, they may obtain it from other generating companies and
sell it onto the consumer.

To assist the consumer to select which company they wish to use, the
government and its three enforcement bodies responsible for supervision of
the energy market: the Consumer Authority, OPTA and the Nma, have
established a website for consumers: ConsuWijzer. (4)

The website (in Dutch) supplies detailed information on all the electricity
suppliers including how their electricity is produced (5). 

I have examined each of the companies listed on this consumer site and this
is information supplied about the method of generating electricity. 

======
Name of company, source of power in percentage terms. Some have yet to be
confirmed by the regulator.
======

Anode - still under validation 
Atoomstroom Atomic Power - still under validation 
Caplare - Water 100
De Ned. De Ned. Energie Maatschappij - Water 100
DELTA -Natural Gas 38.6;  Coal 19.0; Nuclear 12.7; Other 2.1; Wind 13.8;
biomass 13.8
DGB Energie - Natural Gas 56.6; Coal  30.3; Nuclear  9.2; Other 2.6; Wind
1.2
Dong Energy - Natural Gas 20.6; Coal 8.8;  Nuclear 2.8; Other 1.2; Wind
1.6; Water 59.1; Biomass - 5.8
E.ON - Natural Gas 37.8; Coal 16.2; Nuclear 5.2; Other 2.2; Wind 17.8;
Water 16.3; Biomass 4.5
Electrabel - still under validation 
Elektran - water 100
Eneco - Natural Gas 69.3; Coal 4.6; Nuclear 1.5; Other 0.6; Wind 3.6; Water
16.8; Biomass 3.5
Energie - direct - Natural Gas  58.0; Coal - 24.0; Nuclear 8.0; Other 3.0;
Wind 2.0; Water 1.0; Biomass - 4.0
Essent - Natural Gas 36.0; Coal 15.0; Nuclear 5.0; Other 2.0; Wind 12.0;
Water 9.0; Biomass 21.0
Frivius - Wind 15.0; Sun 0.04; Water 70.3; Biomass 14.6
Green Choice - Wind 21.0; Sun 0.5; Water 47.0;  Biomass 31.5
HVC Energie - Biomass 100
MAIN Energie - Natural Gas 46.8 ;Coal  20.1; Nuclear 6.4; Other 2.8; Water
23.9
Nuon - Natural Gas 51.8; Coal 24.1; Nuclear 6.4; Other 5.3; Wind 6.3; Sun
0.02; Water 5.6; Biomass 0.5
Oxxio - Natural Gas 13.4; Coal 5.8; Nuclear 1.8; Other 0.8; Wind 3.7; Water
74.4; Biomass 0.1
Qwint - Wind 100
RWE Energy - Natural Gas 45.5; Coal 12.9; Nuclear 4.7; Other 5.9; Wind
29.4; Water 1.6
United Consumers Energie - Natural Gas 70.2; Coal 22.0; Nuclear 3.6; Other
2.0; Wind 0.2; Water 1.6; Biomass 0.4
Westland Energie - Natural Gas 60.0; Coal 25.0; Nuclear 8.0; Other 3.0;
Water 3.0; Biomass 1.0
Woon Energie - Wind  4.7; Water - 95.2; Biomass - 0.1

As for the power generators, you may wish to explore these fact files on
the 10 largest generators in the Netherlands. The data comes from 2007 with
a 2009 update.
http://somo.nl/publications-en/Publication_2673/?searchterm=factsheet

Sources
(1) "Transmission System Operator and administrator of the national
high-voltage grid, TenneT is in charge of the ‘highways’ of the Dutch
electricity grid, which interconnects all regional grids and the European
grid. Besides managing the grid, we also monitor the reliability and
continuity of the electricity supply in the Netherlands."
http -//www.tennet.org/english/index.aspx

"The national high-voltage grid consists of four types of high-voltage
lines and cables - 380 kilovolt (kV), 220 kV, 110 kV and 150 kV. These are
the standard voltage levels used in Europe for the transmission of large
quantities of electricity ...
TenneT manages the 380 kV and 220 kV grids throughout the Netherlands and
the 150 kV grid in the province of Zuid-Holland. All high-voltage lines and
cables are connected to one another via substations. The high-voltage grid
branches off into 27 regional distribution grids. The distribution grids
are operated by the regional grid administrators and transmit electricity
to the end-users."
http://www.tennet.org/english/tennet/publications/technical_publications/chart_national_transport_grid.aspx

Map of the National grid 
http -//www.tennet.org/english/images/Netkaart%202008_tcm43-17191.pdf

(2) http://www.stedin.net/Pages/Default.aspx

(3) "TenneT, the Dutch Transmission System Operator, is planning to replace
a large transformer in the substation that supplies electricity to central
Rotterdam. The transformer in question converts high-voltage electricity
(150 kV) supplied by the national grid to a lower voltage level (25 kV) for
further distribution throughout central Rotterdam. Stedin the regional grid
operator responsible for distributing electricity from the transformer to
users in their homes and businesses"
http
-//tdworld.com/projects_in_progress/announcements/tennet-rotterdam-transformer-1108/index.html

(4) http://www.consuwijzer.nl/

(5) http://www.consuwijzer.nl/energiewijzer
List of companies 
http://www.consuwijzer.nl/EnergieWijzer_Start


I hope this answer your question, if it does not please do not hesitate to
ask for a clarification.

Phil
answerfinder