Power supply

Power supply is one of Balslev's core competencies

We have significant experience and a wide rage of competencies within virtually all areas related to power supply:

  • High and low voltage systems
  • High voltage cables
  • Transformers
  • Switchgear installations
  • Relay protection
  • UPS and diesel generators
  • Short-circuit calculations
  • Selectivity
  • Network analysis
  • Sustainable energy technology

Our competencies and services within these areas are described in more detail on the following pages.

With Balslev as a co-operative partner on power projects, customers always receive a thoroughly prepared project, which meets their requirements, and which we see through right to the end.

Our highly experienced employees take care of all areas and tasks related to power supply, for new installations as well as upgrades and extensions:

  • Preparation of material for tenders and quotations
  • Contracting of developers
  • Project documents
  • Project management
  • Budget control
  • Test and commissioning.
Analysis and solution proposals to power supply problems

When customers draw on our competencies to analyse prolems or irregularities in their power supply, we thoroughly investigate and document the actual problem in one or several reports, depending on the nature and extent of the problem.

Our final report always contains one or several suggestions to solve the relevant problems plus a budget estimate, if desired.


From consumer driven to intelligent power production.

Today, a sufficient amount of electricity supplied to the consumers is secured by adjusting the power plants' production to the immediate demand. However, with an increasing share of decentral power production from wind mills, combined cycle power plants and solar cells it gets more and more challenging to manage this adjustment.

A possible solution could be to adjust the consumption to the actual available amount of electricity delivered to the grid. However, this requires a wide ranging modification of the electricity grid's infrastructure, among other things with regards to control and adjustment of building installations such as heat pumps.

From political hold there is a wish to push forward the implementation of intelligent solutions for the electricity grid's infrastructure - socalled SmartGrids.

SmartGen - an EU research program

Balslev participate together with 3 other European partners in the SmartGen project, a part of the EU-supported research program for SmartGrids: ERA-NET. The scope is to quickly and efficiently be able to identify the optimum location of a plant for decentral power production within an electricity grid using SmartGrid technologies (SGTs). These are e.g. technologies, which are able to adjust (increase or reduce) the power consumption and production to the actual conditions i.e. whether there is a surplus or deficit in the electricity production.

Balslev is in charge of the Danish part of the SmartGen project:

  • Development of a socalled SGT-model for heat pumps
  • Description of a few additional SGT-models
  • A case study, which is to demonstrate the opportunities for future grid planning using intelligently controlled loads, i.e. whether secure grid planning is possible on a randomly selected 10 kV grid, taking into account the intelligent control of selected loads
  • Identification of the requirements for an SGT-model as well as for future electricity simulation programs.

Balslev is, together with DTU the Technical University of Denmark, Risø (the Danish National Laboratory for Sustainable Energy), the Danish Energy Association plus others, responsible for the iPower project under SPIR (Strategic Platforms for Innovation and Research) under The Danish Agency for Science, Technology and Innovation and the Danish Council for Technology and Innovation. The scope is to analyse the electricity grid's demands with regards to information, control, implementation and security of supply when large amounts of electricity from sustainable but fluctuating energy sources like wind power and solar energy (photovoltaic solar cells) are integrated into the grid.

The iPower project investigates the communication, control and integration of small scale industries and residential housing into the electricity grid. The project is divided into 4 parts:

  1. Domestic Demand Response
  2. Industrial Demand Response
  3. Distribution Grid Operation
  4. Control and Market Operation

Part 1 and 2 is focussing on the flexible consumers. Part 3 is dealing with the distribution grid (typically 10 kV). Part 4 is dedicated to the development of models and input for simulations and estimations of consumer behavioural patterns along with methods for adjustment and control.

Balslev's key focus areas are the time constants for heating and cooling i.e. how long is it possible at a certain outdoor temperature to turn off the heating/cooling in a building, and for how long does the heating has to be turned on. Another area of interest is input for calculation models for the distribution grid, and for electric components such as auxiliary heaters for heating tanks.

AC drive

Balslev handles all tasks related to the installation of AC drives for speed control of motors in machinery and industrial installations.

Our power engineers posess wide competencies and solid experience in designing solutions and implementing AC drives in all sizes, both at low and medium voltage levels.

"AC drive" is the term for an electrical motor and frequency transformer, which regulates and controls a motor. Such drives are typically used in ventilation systems, pumps, machines and transport systems.

We support our customers with a number of services e.g.:
  • Preparation project and tender documents
  • Handling the quotation stage
  • Contracting
  • Project management
  • Budget control
  • Test and commissioning.
Customers who choose Balslev as their advisor, get a solution which is:
  • Cost-efficient
  • Future proof
  • Energy optimised.

Electrical systems & high voltage

A number of private and public electricity producers draw on Balslev's design and project engineering expertise concerning electrical systems.

Our customers include both producers and distributors of electricity, based on renewable as well as conventional energy sources:

  • Windmill producers
  • Owners and producers of wind parks
  • Grid owners and operators
  • Energy suppliers
  • Industrial companies producing power for own consumption - independent power producers (IPP's).

Our many high voltage engineers have acquired considerable experience within electrical systems from numerous projects. We handle all stages of a project process: Feasibility studies, analyses, tender documents, detailed projects and supervision. Our assignments cover all components and system parts in power producing systems:

  • Transformers and coupling systems
  • Wire and cable systems
  • Distribution system and switchboards
  • Switchgear installations
  • Control, regulation and surveillance systems plus Supervisory Control And Data Acquisition systems (SCADA)
  • Earthing, potential equalisation and lightening protection
  • Foundations and structures.
Calculations, security and alarm systems

In order to strengthen our system designs we also conduct a range of calculations on e.g declines in stress fields, short circuiting and stability, plus the modelling of electrical components for use in dynamic simulations.

We also develop proposals for relay design in coupling systems from 400 V to 132 kV. Based on calculations of faulty currents we develop relay plans and propose adjustments to all system relays. System selectivity is documented via trigger graphs for the relays to ensure that the system is documented as safe.

Last but not least, we provide consultancy services related to various safety and alarm systems.


In order to protect equipment and people, we design simple and complex earthing systems for plants and pipelines for power supply plus oil & gas installations.

Balslevs comprehensive experience and competencies comprise the design, calculation and specification of different earthing systems within the infrastructure, power supply and the oil & gas sector.

We ensure optimum configuration of the earthing system in order to protect electrical equipment plus people in the best way possible.

Our engineers have carried out numerous projects for various types of earthing systems and installations such as.:

  • Railways, where earthing is a part of the trains' propulsion power system and provides protection in case of faults in the conductive installations
  • Power supply e.g. on high voltage and emergency power systems
  • Oil and gas installations, where earthing reduces voltage on e.g. gas storages and pipelines caused by e.g. strikes of lightning.

Projects concerning earthing are performed according to the current national and international standards in this area like DS (Danish Standard), IEC (the International Electrotechnical Commission), and IEEE (The Institute of Electrical and Electronics Engineers).

Backup power systems

When we establish UPS and generator systems to supply emergency power we emphasise aspects like needs analysis, profitability, operational costs and future-proofing.

A backup power system to ensure power supply for vital functions in case of power failure can be either a UPS-system (uninterruptible power supply), a diesel generator system or a combination of both.

Balslev has for many years supported customers in different sectors with the preparation of tender material, inspection on installations and testing of backup power systems.

Focus on profitability, training, maintenance and testing

Initially, we calculate the profitability of installing a backup power system on the basis of a risk and network analyses. Our experts advice the customer on the most suited types of backup power systems for their particular needs.

In close co-operation with our customer and the supplier of the backup power systems we also ensure that maintenance criteria are defined, and that the users are trained.

Regular testing of backup power systems is crucial. For this, we help define the necessary pre-conditions, which will ensure that the customer always has a fully operational backup power system.

Customers who choose Balslev as their sparring partner for the installation of emergency power supply will get:

  • A backup power system which meet their request for a cost-efficient solution
  • A future-proof solution
  • A system with the best suited and most reliable components.

Transformer substations

When private or public companies establish new power supply or want to expand or modernise their existing installations, Balslev helps provide the optimum solution for their specific needs.

Whether a completely new transformer substation is to be set up, or the existing transformer set-ups need to be expanded, we can solve the task for any voltage levels - from 10 to 132 kV.

Dependent on the customer's request and own competencies realted to electrical installations, our power engineers can manage the entire or selected parts of the project e.g.:

  • Preparation of material for tender and quotation
  • Handling the quotation stage
  • Contracting
  • Preparation of project documents
  • Project management
  • Budget and control
  • Test and commissioning.
Focus on safety and co-operation with utility company

The installation and subsequent operation of a transformer substation usually requires a close co-operation with the utility company. To ensure this, Balslev can also help optimise the co-operation and prepare the necessary co-operation agreements.

Safety for people as well as security of electricity supply are important parameters associated with the operation of a transformer substation. We are happy to assist with the required assessments and preparation of eventual projects in order to comply with these requirements.

As the customer's representative we strive to find a solution which is:

  • Energy optimised
  • Economically sound
  • Future-proof
  • Implemented using the most suited components.

Electrical simulations and calculations

We use advanced calculation tools to perform e.g. load flow, short circuit and reliability calculations, selectivity analyses, dynamic simulations and statistical analyses of power supply

When we assist our customers with a range of services within power supply, we use a number of dedicated programmes to ensure operational stability, and to protect people and equipment:

  • EDSA (Paladin DesignBase 3.0)
  • Dynamic simulation software
  • Matlab and Simulink
  • ITEM tool kit
EDSA (Paladin DesignBase 3.0)

The highly developed calculation programme EDSA for calculating the electric circuit is, among other things, suitable for carrying out:

  • “Load flow” in individual or parallel power supply
  • Calculation of short circuit current in all centres (momentary and effective values)
  • Selectivity analysis
  • Harmonious and dynamic electrical system calculations

Get more information at www.edsa.com

Dynamic simulation software

We use one of the leading tools to calculate and simulate production, transmission, distribution and industrial systems. It integrates all necessary functions and combines reliable and flexible system modelling capacities with algorithms and databases. The programme helps us to carry out:

  • EMT simulations for three, two and single phase AC and DC systems
  • Protective simulations: Protection of electrical equipment and co-ordination of protective equipment
  • Static and dynamic tension stability
  • Fault analysis.
Matlab and Simulink

Matlab is an advanced calculation and programming tool, which, among other things, provides the possibility to do:

  • Data analysis and visualisation, e.g. temperature measurements in wind turbines
  • Static component modelling, e.g. generators and cable modelling

Simulink is based on Matlab programming language, and is used e.g. in:

  • Regulation and stability calculations for automation solutions
  • Testing and verifying electrical components

Read more about these programmes at www.mathworks.com

ITEM Tool Kit

Software for analysis of the reliability of radar systems, industrial systems etc. The program uses globally recognised standards and methods to analyse components, systems and projects. It provides the possibility to:

  • Analyse individual systems and components from a complete system approach
  • Optimise the design specifications in terms of the choice of components and increased security.

The computer program FEBDOK helps ensure good electrical configuration. It also gives professionals documentation for their configuration plus access to documents which can be used in the final quality check of fittings and thereby serves as documentation that the installation has been done correctly.

  • Calculates short-circuit current/faulty current
  • Calculates interface tension and voltage drop
  • Dimensions cables, tracks and overcurrent protection
  • Controls the protective devices' breaking capability and disconnection time
  • Controls selectivity (selectivity analysis)
  • Controls backup/cascade protection of protective devices
  • Provides necessary documentation for electrical inspections, customers and electricians.

Read more about FEBDOK (in Danish)

Specific projects
  • EnBW windmill park Baltic I
  • Copenhagen Airport
  • Statoil refinery
  • Vestas
Fields of application
  • Power supply
  • Wind energy
Software overview
  • EDSA (Paladin DesignBase 3.0)
  • Dynamic simulation software
  • Matlab and Simulink
  • ITEM Tool Kit


Carsten Sass Husum
Områdechef, Elektroteknologi
7217 7217


The Silo Østre Gasværk Teater PowerLabDK University of Copenhagen Amager The Vejroe Project CPH University Hospital Nødstrømsanlæg på Rigshospitalet EnergyLab Nordhavn