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October 29th

Maintenance as a tool to increase the electric power availability

Leonardo Energy launches its case study series with this first one about maintenance as a tool to increase the electric power availability, reduce running costs and prevent damage to people & property by Matteo Granziero, Socomec.

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October 24th

Power Quality monitoring in India

Demonstrating poor quality

For electricity consumers in India, supply interruptions and low voltage levels are a constant source of concern. Utility companies recognize the problem and are now making major investments to improve Power Quality (PQ). However these improvements are coupled to tariff increases. To verify if real PQ improvements have been made, effective monitoring of the supply quality is crucial.

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October 23rd

A study of voltage sags in electric motors

One of the biggest problems in Power Quality is the disconnection of electric motors due to the presence of sags. In order to study this phenomenon it became necessary to build a sag generator to, for example, develop immunity curves for induction motors as well as for synchronous motors. In this way it is possible to evaluate the quantitative impact of sags in these machines. This paper also analyzes the effects in current, torque and speed caused by sags, in particular A, B and C types.

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PFC units sizing in steel factory harmonics environment: a case study

This paper deals with PFC units design related problems in case of installation in harmonics rich environments: in particular the paper contains an overview of sizing approach used in a real case of PFC units design for installation in a steel factory where new PFC units installation has been necessary after a fault with catastrophic consequences for the existing ones. The document contains a report on stresses calculation on PFC units due to harmonic currents generated by non linear loads installed in the above mentioned plant.

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Field Demonstration on Multiple Power Quality Supply System in Sendai, Japan

We present the progress of a new project, a field demonstration of a multiple power quality supply system. The project is the first trial to take place in Japan in the area of power quality concepts and solutions. For this project, NTT Facilities developed and installed a multiple power quality supply system that has the capability to feed four classes of alternative current (AC) and one of direct current (DC) power while meeting various customer requirements.

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Blue Energy

When a river runs into the ocean and fresh water mixes with saltwater, huge amounts of energy are unleashed. Unlike violent torrents in a waterfall or steaming hot geysers, the energy released cannot easily be seen from the banks of the estuary. Nevertheless, the energy is there, and everyone who has tried to separate salt from seawater knows that large amounts of energy are needed.

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October 16th

Energy security and critical infrastructure resilience

The Czech Republic has a well developed national transmission grid. Nevertheless, several emergency situations occurred last year (2006). The energy security discussion between public and private sector was accelerated. The Ministry of the Interior and the Ministry of Regional Development as well as several Regional Governments sponsored several studies and research projects into how to improve population protection as well as critical infrastructure protection.

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October 15th

Propagation of Unbalance in Electric Power Systems

Power quality has become an important issue for electric power engineering. Nowadays, the distribution electric networks have unbalanced operating regimes, mainly produced by the great number of single-phase loads. Unbalanced line currents produce unbalanced voltage drops on the three phases of the supply system. Consequently, the voltage system within the supply network will become unbalanced.

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Insulation and Heating

Buildings account for 40% of energy consumption in Europe, so their inherent efficiency is very important.

Efficient space heating requires a properly insulated and sealed building, together with a correctly sized heating system. The choice of system is also important; best practice includes gas-fired condensing boilers and ground-water heat pumps.

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October 3rd

Lighting Design & Techniques - Completing the series

By Anne Rialhe, AERE & Pascal Lenormand, Incub

Part 1 - Lighting & Human Life

This is the first article in a series of three in which we will focus on the relationship between lighting and human life. This topic is much broader than merely ‘ensuring vision’. After defining some important terms and measurement units, we will discuss how the quality of lighting interacts with and effects human behaviour.

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