Diesel fuel and heating oil are chemically identical. »Only« the tax rate the final consumer has to pay is (very much) different. But obviously the difference looks a lot different for railway fuel, i. e. the difference makes no difference there. This smart, modern German railcar of the Baureihe 612 series (google for »BR 612« for photos), which comes as a twin carriage (4 bogies / 8 axles) with 2 diesel engines (of 560 kW each!), has 2 separate tanks for engine fuel and for heating oil. But obviously it doesn’t matter what you fill in where.

If you have had the opportunity to join a locomotive driver on the predecessor, BR 610, then you may have seen that this series still used to have an engine power indicator, which was omitted later in the 611 and 612 series, and that the full power (»only« 2*525 kW on the 610 version and 2*540 kW on the 611 version) is only used for accelerating the weighty vehicle and for travelling uphill. To sustain its constant maximum permissible speed of 160 km/h in the plains an engine power output level of ≈35% is enough. Several kilometres before the next stop the locomotive driver disengages the engines, and the railcar rolls and rolls and rolls, you just don’t realize any drop in speed. Then the brake is operated, the train brakes and brakes and brakes, while the engines keep on running with their (though low – but technically at least during these stages totally avoidable) stand-by loss. But the »waste« heat is needed for the passengers inside – while simultaneously the brake disks need cooling.

 

By Guy Kasier

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A new 'Compendium of Champions' by the ACEEE

The American Council for an Energy Efficient Economy (ACEEE) recently published a compendium of exemplary energy efficiency programmes. It is the second report of this kind; the first being completed in 2003. The Compendium contains the profiles of 90 of America’s leading energy efficiency programmes sponsored by the utility sector (electricity and natural gas). They are either funded by utility rates, public benefits charges, or other similar utility revenue mechanisms. The 90 programmes were selected from a large number of nominations.

Together, the selected programmes achieved annual savings of 2,400 GWh of electricity, 400 MW of peak demand, and 125 million therms of natural gas (= 13.185 TJ or 3.663 GWh).

By K Hirose et al

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. The system also has three types of distributed generator (DG): gas engine sets, fuel cells, and photovoltaic panels. The rated capacity of the DG’s is just 1 mega-watt. NTT Facilities started the project in Fiscal Year (FY) 2004 and plans to continue it for four years. We have been testing the multiple power quality supply system in the field since October 2006. Some sets of test data and an analysis using the data indicate that the developed system meets all the requirements for distributed generator related plants and has additional benefits. This paper presents the results of a review of the project’s first three years, our plans for the future, and an idea about how to assess the power quality data that the project will generate.

By C Gonzalez et al

The integration of photovoltaic generation systems into power networks can cause both benefits and drawbacks. However, utilities have to control and operate their systems properly, in order to assure the availability and quality power supply to the users. Therefore, utilities should consider technical constraints and existing regulation in order to assess the impact of photovoltaic systems and limit their integration. On the other hand, regulation includes few operation constraints and they are not implemented in current software analysis tools.

In the present paper a tool for assessing the impact of PV integration on low-voltage networks is described. The voltage fluctuation, the inversion of the power flow and the increase of short-circuit capacity are the problems considered in the proposed tool. Further work will focus on harmonics distortion.

By F J Santiago et al

Many topics are arisen nowadays in an effort to mitigate the constraints appearing on the energetic supply issue. One of them is the idea of concentrate the generation and consumption in certain areas defined as μGrids. All, reliability, quality of supply, energetic efficiency, economic profitability…, must be considered as a reality on the development of this new concept.

Supported by the rapid development of the power electronics, and aimed by the fact that an important part of the present domestic sector and of the small generation resources are based on direct current features (DC), the old Edison’s paradigm of a DC infrastructure comes again into discussion. On this paper, some advantages derived from the use of a low voltage network supported on a DC voltage are discussed, at the time that different scenarios where the DC system could result in a realistic alternative are proposed.

No doubt it is good that the European Union is able to enroll as many as possible into the forces to make positive changes for the future. Now the “Covenant of mayors” is underway, and it is certainly good to secure commitments from high-level politicians and important cities all over Europe.

But why is there not a stronger connection with the Concerto-project that really covers the full scope of technology, policy-making and customer response? Yes, we need as many hands as we can find; yes, we need high level commitment, but do we not also need to make full use of all experience that can be found?

Concerto is a profound project with 45 municipalities already directly involved and several more adjoined as observers, both other communities and several academic institutions. They cover a truly broad spectrum of technologies both for demand and supply side, but they also cover an even more important category of issues, the aspects of decision making and of user attitudes when new technologies shall be put in place. This knowledge should be a natural and integral part of the job when mayors are enrolled. Unless, of course, the mayors are there only to shine!

Concerto brochure

Some years ago, Energi-Citées took an initiative to arrange study-tours to important municipalities. This is an interesting way to attract politicians and establish more and newer forums for information exchange. Let us hope that something similar can be arranged to glue all the experiences together rather than making them stand alone on their own turf.

Based on a Discussion Webinar, Friday 25th April 2008

The EU directive on the labelling of household appliances is a success. Since its entry into force in 1992, efficiency of appliances has risen considerably. With directive currently under revision, there is an opportunity to take the next step.

Should this programme also be extended to other products such as industrial equipment, for example? Or even to entire systems such as buildings? But maybe there are already too many labels on the market, to the confusion of consumers? How can the accuracy of label attribution be monitored, and should labelling programmes be accompanied by Minimum Efficiency Performance Standards (MEPS)? Finally, should labelling promote the best products or phase out the most inefficient products from the market?

These and other questions were addressed in a Discussion Webinar on 25th April 2008. Below are a few of the highlights from that discussion.

The European labelling scheme

Refrigerators are an excellent example demonstrating the impact of the EU labelling directive. The majority of refrigerators sold have shifted from efficiency categories D and E in 1992 to A and B in 2003. The categories with lower efficiency, E, F and G - about 50% of the market share in 1992 - have almost disappeared.

However, the current directive has a few shortcomings. Unlike safety labels, efficiency labels are not compulsory for all classes of electrical equipment. Furthermore, only “cold appliances” (freezers and refrigerators) are subject to MEPS.

The following article is the result of an interview with François and Benoît Henriet of the Belgian wind energy development company Greenwind. The article is published as an eBook so you can scroll the different pages using the titles below. The full article is also available as a PDF for download.

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The wind energy industry is booming worldwide, favoured by ambitious targets for renewable energy, various subsidy mechanisms, and rising prices for fossil fuels. This does not mean however that wind companies have struck gold. A wind development project is a complex affair with many barriers and one requiring favourable climatic and geographical conditions that are available in only relatively few countries in Europe. Leonardo ENERGY talked with François and Benoît Henriet of the Belgian wind development company GreenWind about the difficulties in finding appropriate wind park sites and about the future potential for wind energy in Europe.

 

 

 

Or is it a tool used for generating energy savings?

In the eighties and nineties, the energy consumption of ICT appliances was not an issue. At that time, it appeared to be miniscule in comparison to other energy consumption. In recent years however, this has changed dramatically. The ICT sector has matured and today’s huge server rooms can hardly be called minor energy users. Moreover, rising energy prices and climate change concerns have raised awareness of stand-by losses of communication appliances and PCs. As a result of this, the ICT sector is increasingly criticised for its steeply rising energy consumption.

It is a fact that the carbon footprint of the ICT sector has been rising and is now estimated to be 2% of global emissions, but the ICT sector cannot be viewed separately from the rest of the economy. The American Council for an Energy-Efficient Economy (ACEEE) has recently published a study ('Information and Communication Technologies: The Power of Productivity') stating that the innovative effects of ICT have contributed to an economy-wide reduction of the energy intensity in the U.S.

Power Injection Control System and Experimental Model based on Manufacturer Characteristic Curves for a Photovoltaic Generation Amparo Rico, Enrique Romero Cadaval, María Isabel Milanés Montero Mathematical Model of DC Motor for Analysis of Commutation Processes Zygfryd Glowacz and Witold Glowacz Stochastic Estimation of Voltage Sag Due to Faults in the Power System by Using PSCAD/EMTDC Software as a Tool for Simulation Nita R. Patne and Krishnarao L. Thakre Passive Filter Design for Three-Phase Inverter Interfacing in Distributed Generation Khaled H. Ahmed, Stephen J. Finney and Barry W. William The Use of the SSC as Reactive Power Compensator Federico Delfino and Renato Procopio Three-level Modulation Techniques to Reduce Instantaneous Common Mode Voltage in Induction Machines J. Cusidó, A. Luna, S. Busquets, J. Bordonau, P. Rodríguez, L. Romeral Influences of a “Hybrid Grid” on the Network’s Voltage Quality and Supply Reliability Sharmistha Bhattacharyya, Johanna MYRZIK, Jos MEUWSEN Wind Turbine Harmonics Caused by Unbalanced Grid Currents Klaus-Dieter Dettmann, Steffen Schostan, Detlef Schulz Electromagnetic Coupling of the Electrical Drive – EMC (Part I) Irena KOVÁCOVÁ, Dobroslav KOVÁC Quasi-Instantaneous Generation of Reference Signals for Hybrid Compensator Control Leszek S. Czarnecki

Edited by Prof Z Hanzelka University of Mining and Metallurgy

By P Goldstrass et al

A change in technology is taking place in power factor correction. Fast changing loads demand new, dynamic solutions that offer additional technical advantages and economic benefits. In this paper basic advice for the composition of a dynamic power factor correction (PFC) system is given. As example the setup and performance of a dynamic PFC system for wind turbines, named DynaWind 6000, is presented, that excellently meets the typical requirements to PFC installations in this application.

Emissions of nitrogen oxides (NO_x) and sulphur dioxide (SO₂) from large combustion plants (LCP) could have been considerably lower in 2004, a report presented today by the European Environment Agency says.

Power plants burning coal, oil and/or gas are significant contributors to European emissions of NO_x and SO₂ — two important acidifying pollutants. Improving the environmental performance of LCPs by applying the best available techniques could have reduced NO_x emissions by up to 59% and SO₂ emissions by as much as 80% in 2004, the report says.

Nitrogen oxides and sulphur dioxide emissions could have been 20% and 61% lower respectively if the facilities had met the emission limits set in the LCP Directive, whose purpose is to reduce emissions of acidifying pollutants, particles, and ozone precursors.

The report Air pollution from electricity-generating large combustion plants is based on data from 450 electricity-generating LCPs across EU-25 in 2004. The LCPs covered by the report account for more than 70 % of the emissions of NO_x and SO₂ from this sector and are included in the European Pollutant Emission Register (EPER).

Combustion facilities in EU-25 amount to 54% and 18% of the reported SO₂ and NO_x emissions respectively.

Sharmistha Bhattacharyya, Johanna MYRZIK, Jos MEUWSEN

The electricity is a basic need for functioning of modern society. In the deregulated electricity market, delivering quality power to the clients is a challenge for the utilities. In this paper, a “hybrid grid” is discussed that consists of centralized generations and localized distributed generations which may be comprised of small-scale conventional and sustainable sources. Energy storage option is also integrated in the hybrid-grid. Simulations are done on a test network, using “Power-Factory” software. It was found from the analysis that voltage quality and power supply availability of a hybrid-grid can be improved by proper selection of energy storage system along with protective and control devices.

Klaus-Dieter Dettmann, Steffen Schostan, Detlef Schulz

For wind turbines that feed into public grids limits for voltage and current harmonics must be assured. To verify that the actual levels are valid, measurements are necessary. Problems can occur to determine which part of these harmonics has its origin in the wind turbine. It is shown that also harmonics which originally have zero sequences can be transferred over a delta-star-transformer, if the currents of the wind turbine are asymmetric due to unbalanced loads. Measurements in an existing wind turbine configuration are discussed, which confirm the described effects.

Karolien Verhaegen, Leonardo Meeus, Bram Delvaux and Ronnie Belmans

In 2001, the European Commission formulated an ambitious target of 21% of total community electricity consumption to be generated with renewable energy sources by 2010. Moreover, national indicative targets per Member State were specified. In practice, the latter are implemented in all Member States as national production targets, achievable exclusively through an increase of the domestic production of electricity produced from renewable energy sources (hereafter “RES-E”). However, in this article it will be shown that this is not in line with the EC's intent. Looking at the legislative process resulting in the Directive on the promotion of RES-E, it is demonstrated that instead the EC aimed for European trade in renewable electricity through national consumption targets.

It is shown that the legislative process has resulted in confusion on both the nature (absolute or proportional figures) and the subject (consumption or production) of the RES-E targets that are being aimed for. Despite the EC's attempt to clarify this confusion, the reality of national production targets remains, hindering the attainment of the European RES-E target in the most cost-efficient manner.

For a long time, the dominanting has been that taking action against climate change is a risky business for a country and its industry, an idea underpinned by some economic thinking saying that unilateral action is at best useless and that policy measures must be strictly targeted. One problem requires one measure only, otherwise, measures will be diluted and even counterproductive. Nowadays, both politicians and their advisors have a different tune. Actions may not be as costly, early actions may give an advantage and policies may be mutually supportive. Could it be the Stern Review that has turned into a Stern Tsunami?

When you are lucky enough to have the insight into the interior technical details of a German ICE 2 high-speed railcar, you may realize that the main transformer has 7 output windings. Next to 4 windings with a 1 MVA output for the 4 inverter drives, you will find 3 windings for ancillary supplies, among them one for the carriage heating with an output rating of 500 kW!

But also without such opportunities, you only need to look around at the railway stations, and you will find quite a number of connection points for train pre-heating. Since most passenger trains in Germany are either operated electrically or they come as railcars with integrated diesel engines, these connection points are mostly no longer in use today (as the label tells you here for example). But note that the voltage ratings are 1500 V, 2000 V or 3000 V! This is not done for fun but because the heating of (especially old) trains guzzles tremendous lots of energy. This remains to be included into considerations about how to make railway transportation even more energy efficient, which despite all it already is, but there are still significant potentials left.