i.e. remote surveillance, can help in constant monitoring and real time information
about what is happening at a site. Key to such planned predictive maintenance is the
increased deployment of sensors in offshore wind turbines. Modern offshore wind
turbines, particularly those that are custom built for offshore, will contain a huge
number (>1000) of sensors in key components. The ongoing Dutch Offshore Wind
Energy Services (DOWES.nl) project focuses on developing an innovative information and communications technology (ICT) system to manage offshore wind
parks in the Den Helder region (2008–2014). The DOWES management plan aims
to lead to high wind farm availability at minimum cost. The ICT system will be
capable of reading the sensors on the wind turbines using remote control, making
use of the most up-to-date science.
It is possible to manage and maintain offshore wind parks in various ways.
DOWES aims to safeguard offshore wind parks from a distance/on land. Constant
monitoring of the state of the wind turbines can facilitate timely information of the
right people. This can aid in making cost-effective choices and carrying out
maintenance optimally. In the long run such systems are expected to increase the
manageability of offshore wind parks and reduce maintenance costs.
4.2.5 Analysis of Operation and Maintenance Costs
To get more insight in the O&M cost structure of OWFs, the total O&M costs are
split over specific O&M disciplines. It starts with the breakdown of the operational
expenditures (OPEX) (Fig. 4.1).
This breakdown shows that the O&M costs represent 53% of the OPEX (15%
“Operation” + 38% “Maintenance”). In the Asset Management Control
(AMC) approach (Stavenuiter 2002) the discipline “Maintenance” is considered to
be the combination of all technical, logistic, administrative and managerial actions
during the life cycle of an asset/object, intended to retain the asset or restore it to a
state, in which it can perform the required function. Therefore, the activity “Port
Activities” is considered a part of “Maintenance”. For the UK’s seabed, the Crown
Estate applies license fees. However, this aspect is not applicable for the offshore
wind industry in the Netherlands. For this reason the cost for license fees is also
included under “Maintenance”. “Other cost” which are not specified by Board
(2010; Fig. 4.3) are distributed among the O&M disciplines: 5% are placed under
“Operation” and 7% under “Maintenance” since this discipline holds more variable
and unspecified costs.
The next objective is to validate a realistic average annual O&M cost for offshore wind farms. For this purpose, a specific annual O&M cost analysis has been
carried out. Figure 4.4 illustrates the spread of O&M cost, as applied in several
reports (Board 2010; Feargal 2009; Pieterman et al. 2011; Kjeldsen 2009; Musial
and Ram 2010; Rademakers and Braam 2002). The total annual O&M cost varies
between 15 and 45 €/MWh. The cited reports do not mention the size of the wind
farms, nor the distance to shore. It seems likely though, that these aspects have great
102
C. Röckmann et al.
about what is happening at a site. Key to such planned predictive maintenance is the
increased deployment of sensors in offshore wind turbines. Modern offshore wind
turbines, particularly those that are custom built for offshore, will contain a huge
number (>1000) of sensors in key components. The ongoing Dutch Offshore Wind
Energy Services (DOWES.nl) project focuses on developing an innovative information and communications technology (ICT) system to manage offshore wind
parks in the Den Helder region (2008–2014). The DOWES management plan aims
to lead to high wind farm availability at minimum cost. The ICT system will be
capable of reading the sensors on the wind turbines using remote control, making
use of the most up-to-date science.
It is possible to manage and maintain offshore wind parks in various ways.
DOWES aims to safeguard offshore wind parks from a distance/on land. Constant
monitoring of the state of the wind turbines can facilitate timely information of the
right people. This can aid in making cost-effective choices and carrying out
maintenance optimally. In the long run such systems are expected to increase the
manageability of offshore wind parks and reduce maintenance costs.
4.2.5 Analysis of Operation and Maintenance Costs
To get more insight in the O&M cost structure of OWFs, the total O&M costs are
split over specific O&M disciplines. It starts with the breakdown of the operational
expenditures (OPEX) (Fig. 4.1).
This breakdown shows that the O&M costs represent 53% of the OPEX (15%
“Operation” + 38% “Maintenance”). In the Asset Management Control
(AMC) approach (Stavenuiter 2002) the discipline “Maintenance” is considered to
be the combination of all technical, logistic, administrative and managerial actions
during the life cycle of an asset/object, intended to retain the asset or restore it to a
state, in which it can perform the required function. Therefore, the activity “Port
Activities” is considered a part of “Maintenance”. For the UK’s seabed, the Crown
Estate applies license fees. However, this aspect is not applicable for the offshore
wind industry in the Netherlands. For this reason the cost for license fees is also
included under “Maintenance”. “Other cost” which are not specified by Board
(2010; Fig. 4.3) are distributed among the O&M disciplines: 5% are placed under
“Operation” and 7% under “Maintenance” since this discipline holds more variable
and unspecified costs.
The next objective is to validate a realistic average annual O&M cost for offshore wind farms. For this purpose, a specific annual O&M cost analysis has been
carried out. Figure 4.4 illustrates the spread of O&M cost, as applied in several
reports (Board 2010; Feargal 2009; Pieterman et al. 2011; Kjeldsen 2009; Musial
and Ram 2010; Rademakers and Braam 2002). The total annual O&M cost varies
between 15 and 45 €/MWh. The cited reports do not mention the size of the wind
farms, nor the distance to shore. It seems likely though, that these aspects have great
102
C. Röckmann et al.