Electricity

At the 2008 Light & Building fair in Frankfurt a company producing electronic starters for fluorescent lamps with magnetic ballasts exhibited a new demo panel. The panel compares 6 systems:

1. An uncompensated 58 W fluorescent lamp with a class B1 magnetic ballast.
2. A 58 W fluorescent lamp with a class B1 magnetic ballast and serial compensation (forming a lead-lag compensated pair with the former), whereas the capacitance can be selected to match the official rating of 5.2 µF or to be reduced to 4.6 µF, at which the actual current value will more or less equal that of the uncompensated lamp.
3. A 58 W fluorescent lamp with a class B1 magnetic ballast and parallel compensation (7.0 µF).
4. A 58 W fluorescent lamp with a class B1 magnetic ballast but which is rated 240 V instead of 230 V.
5. A 58 W fluorescent lamp with a class A2 electronic ballast.
6. A 58 W fluorescent lamp with a class B1 magnetic ballast and a Voltage Optimizer “EOS” 900 VA 230 V/195 V by www.ipsi.dk.

Each system is equipped with a multimeter panel displaying the incoming voltage, active power and reactive power. All of them are fed from a common variable transformer, except No. 6, which is connected directly to the supply.

A seventh meter displays the overall values, so as to display the good compensation performance of the lead-lag circuit.

It can also be seen that when the voltage is set to a level at which the input power to the system No. 5 with the electronic ballast is equal to that of any “normal” B1 configuration, which is the case at around 215 V, there is no visible difference in light output. This raises doubts about the possible energy efficiency improvements with electronic ballasts. At least the potential seems to be rather limited against the best commercially available magnetic ballasts.

On top of this, switching system No. 2 accordingly shows that the electronic starters used in the panel reliably start the lamp even if the voltage drops to 190 V and at the same time the serial compensation capacitance is reduced below the official rating.

But expensive to implement

In recent years, peak summer demand for electricity has been rising more steeply than the average energy demand, especially in sunny countries where air conditioning is becoming standard.

Contrary to what you might expect, electricity generation and retail companies are not pleased with these consumption peaks. With the current pricing model, the cost of providing the marginal peak kWh is often higher than the revenue. Electricity transmission and distribution companies also see a high peak demand as a burden since it requires extra transmission capacity. A high peak demand is also negative from an environmental point of view, because it often requires the use of peak power production units with a poor environmental performance.

New Decree 22/1/08 n. 37 (G. U. 12/3/08 n. 61) replacing 46/90 law has become effective.

New 22/1/08 Decree "Regulation for implementation of Art. 11-quaterdecies, paragraph 13, letter a of law N. 248, December 2, 2005, related to reorganization of regulation on installations inside buildings" has been published on the Italian Official Gazette, (12/03/08, N. 61)

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Occasional reason for complaints:

Conflicting statements on the same thing in different standards

by Stefan Fassbinder

Different standards often make divergent statements on the same part or component of an installation. This is because, firstly, one standard deals with electrical safety (e. g. IEC 60364-5-54), another one with functionality and EMC (e. g. IEC 60364-4-44) and possibly yet another with lightning protection (e. g.  IEC 62305).

In many cases, the limits given in standards are mere estimates, so the respective bodies, since they all consist of technical experts, will always come to similar, but not necessarily the same limit values! Because standardisation, especially on an international level, is a very complex task, there is often a lack of communication between any two (or even more) bodies dealing with the same object from different perspectives. This is how the conflicting statements come about.

The table below gives a compilation of partly conflicting requirements. At present, attempts are being made to overcome these small, technically irrelevant, but all the more confusing deviations. For instance, the following requirements are given in the present Table 54-2 of draft IEC60364-5-54 (64-1610/CD):

Present draft Table 54-2 (64-1610/CD)
	Buried in the soil		Unburied
Type of protection	Cu	Fe	Cu	Fe
Electric shock	See Table 54-1	See Table 54-1	See clause 543.1.3	See clause 543.1.3
Electric shock & lightning protection	16mm²	50mm²	16mm²	50mm²

The NERC 2007 Long-term Reliability Assessment

Last October, the North American Electric Reliability Corporation published its '2007 Long-term Reliability Assessment'. The conclusions of this study are more than a little alarming. The North-American grid is ageing rapidly and it is no longer adequate to cope with today’s energy landscape, containing large quantities of renewable energy systems. Transmission capacity continues to lag behind demand and will need to increase by more than 10 per cent over the next 10 years. According to the Assessment, there is also the need to develop reliable storage capacity to better manage demand.

The cost of building a high capacity, integrated, and smart grid system is estimated to be $100-150 billion. However, the economic impact associated with a failing grid would quickly amount to the same order of magnitude.

The ninth weekly session at the Leonardo ENERGY 3D Forum takes place this Friday November 23th, from 14h00 - 15h00 Europe Daylight Time (Brussels), where you can meet with the Leonardo ENERGY team and other users of the Leonardo initiative inside the 3D forum (check here to convert Brussels time to other time zones).

During the session, you can power-chat (chat in parallel with multiple visitors), talk by VoIP, exchange business cards or browse the pavillons of the 3D world, which is updated weekly. The pavillions comprise virtual stands where you have access to information and 3D models of a number of appliances.

You are also invited to listen to past recorded presentations in the archive room.

During the session, a number of side presentations on sustainable energy topics will be given by Leonardo ENERGY team members. This week, topics covered include 'balancing the electricity system' and 'photovoltaics'.

If you have not yet done so, download & install the 3D World and register for the 3D Forum.

We hope to see you there regularly as our virtual guest in our weekly sessions every Friday, but you are invited to visit and investigate the Leonardo ENERGY 3D Forum at any time.

 

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Removing bottlenecks to allow free trade

Enhancing the European transmission grid is important for three closely interwoven reasons:

• To allow power transport to compensate for the intermittent output of renewable energy systems
• To enable free trade in electrical power within the EU
• To ensure a continuous power supply throughout the EU

In spite of the importance of these changes, grid enhancement is progressing very slowly. There are several reasons for this. First, current European regulations do not allow Transmission System Operators to build up the necessary investment capital to undertake large scale infrastructure works. Second, the environmental impact assessments of overhead lines take a great deal of time. The European landscape is already densely built, so it is normal that each new construction project must be thoroughly investigated regarding its necessity.

While many involved parties have recently been urging faster grid enhancement, this does not mean that no progress is being made at all.

New cross-border transmission lines

This month, the new 700 MW subsea interconnector between Norway and the Netherlands will be inaugurated.

A genuine peer-to-peer, plug-and-play subgrid

As described in a recent post ('Creating microgrids for connecting DG units'), microgrids can be a way to enable high penetration of Distributed Generation (DG) without the need to completely redesign the distribution grid. Microgrids can even enhance the local level of power quality thanks to DG units.

Another study by IEEE focuses on 'extended microgrids'. An extended microgrid consists of a group of radial feeders, each of which include not only loads and a generation unit, but also a storage device.

The extended microgrid is peer-to-peer; the system can continue operating with the loss of any component or generator. It is also plug-and-play; the unit can be placed at any point on the distribution grid without re-engineering.

Concerns about CO2 and climate change are greater than ever. Residential heating is responsible for a considerable part of CO2 emissions that go into our atmosphere.

The objective of this case study is to compare the environmental impact of a heating system using a gas conventional boiler and other using electrical heaters at the point of use. The simulations were made taking into account the conditions for a normal house and a low energy house. Several electricity generation mixes were also used in order to assess the impact of electrical heating in different countries.

The results show that electrical heating has great advantages when clean electricity generation is in place, e.g. using renewable energy sources or nuclear energy.

 

Electric motorcycles are becoming a practical alternative to the conventional “dirty” motorcycles. Although they are very fuel efficient, conventional motorbikes are not equipped with emissions-control technology – SUVs are 95% cleaner.

However, due to advances in battery technology, these can be powered with clean sources of electricity and help reduce oil consumption and greenhouse gas emissions.

Electric motorcycles could become a very attractive solution in countries like China, where motorcycles are very popular in urban transportation. They could have a decisive impact on bringing down the cost of advanced batteries by increasing their market, leading to a faster development of bigger solutions for urban family vehicles.

In the past, the lead-acid batteries used in motorcycles made them very heavy and provided very short range. Current solutions include nickel metal hydride and lithium-ion batteries, which are lighter and more durable. In the past, lithium-ion batteries were not used because of safety concerns: they could overheat and explode. New lithium-ion batteries use phosphate rather than oxide-based electrodes, which makes them more resistant to high temperatures and more difficult to set on fire.

Making use of all the benefits of Distributed Generation (DG)

Distributed Generation (DG) technologies such as photovoltaic cells, wind-power, micro-turbines and fuel cells have the potential to significantly reduce emissions and ultimately perhaps the production cost as well. Connecting them to the distribution grid however is a subject of major concern.

One way of dealing with this could be to take a systems approach, viewing the generator and the associated loads as a subsystem or ‘microgrid’ that can be separated from the main grid. Such a microgrid would operate in parallel with the grid (when connected) or in island mode (when disconnected). It would disconnect from the grid during significant events (faults, voltage collapses), providing UPS services to its loads. If desired, it could also disconnect when the quality of power from the grid fell below certain standards.

Recognizing the very large, growing number of slum residents lacking legal, safety and affordable access to electricity in developing countries, the International Copper Association (ICA), in cooperation with the U.S. Agency for International Development (USAID), launched the Slum Electrification and Loss Reduction Program (SELR) in October 2005. One of the selected cities was São Paulo in Brazil, in which was identified Paraisópolis, a slum area in the middle of the city, to develop a pilot project in partnership with AES Eletropaulo, local utility; Nexans, cable manufacturer and Itaipu, transformer manufacturer.

There is an estimate that 1.6-2.0 billion people do not have access to electricity. The IEA made a survey of the issue and also of some success-stories in electrification in their World Energy Outlook 2002.

But we may have to consider that the problem is bigger than just access. In many places the "losses" (to use a euphemism) are big. Electricity disappears from the lines due to clever connections made by people in need. And even when theft is not the problem electricity may be sold to prices far below the cost. If we ever should design a sustainable system we need to apply more energy efficient solutions but what is the incentive if you do not pay?

Except for low income residential customers and electricity intensive industrial sectors

Energy and environmental specialists alike often argue that electric energy is far too cheap. They are referring to the 'externalities' of electrical generation: in fact the true global cost to society is still much higher than the actual market price. Pressure for higher rate is usually countered by statements from the other side of the argument that higher electricity prices pose a peril for the economy. These individuals argue that higher energy costs would lead to higher prices for goods, which in turn would reduce product demand and cause a negative economic spiral.

Recent data from the U.S. Energy Information Administration (EIA) show that electricity costs and the overall economy are not as closely linked as they once were. The energy consumption used to create the Gross Domestic Product (GDP) in the U.S. has been nearly halved since 1970. Nor do statistics for U.S. states show a correlation between electricity prices on the one side and growth in State Gross Product or changes in unemployment rate on the other.

Denmark has a tremendous experience from wind power in many applications. The major stakeholders have made an exhaustive report about "Key Environmental Issues" in off-shore wind, including some socio-economic angles, which may be useful in discussions about siting and consequences.

 

In some of the comments in Europe (let us be tactful and avoid names) to the issue of climate change and the need for measures, there has been an undertone of self-righteousness, rather than willingness to act. Some have said that many of the European countries are so small that it does not matter what they do. Some have gone as far as saying that focus should be shifted to countries like China, India and Brazil and others. Absolutely, but how?

China has at least put up strong targets and is also pioneering the use of accounting that includes the environmental effects. But has not managed to keep the pace the first of the five years in the latest plan. Still there is hope to get up the speed!

And India is taking assistance from no less than Sir Nicholas Stern! But sceptics say that the man on the street still would like to have some of the goods that are advertised to him to be necessary for a decent living in the industrialised world. Who could blame him?

If we consider these issues of what is right and fair it becomes so much more obvious that the European technology plan focus on sustainable technology rather than only low-carbon that could cement us in vulnerable infrastructures.

ETSO, which is the co-operation of European Transmission System Operators, has published an explanatory note on Demand Response (DR) that contains a survey of the options and some experiences form selected countries. US DOE published a report on the benefits of DR about a year ago and that contains very good graphic overviews Taken together the reader gets the impression that the electricity market still is immature and can be much more developed when (if) customers will be able to exercise choices not only on the supplier but on the amount to be delivered in relation to price (or urgency).

But still the issue remains - who will act to make it happen? The Transmission System Operators obviously have an incentive when congestions shows that the system could break down, but there seems to be a role also for "aggregators" to step in as intermediates. Clever statisticians with a business-mind?

Jos M Wetzer, Sonja Bouwman, KEMA Consulting

In order to anticipate possible hazards in ageing networks, asset managers increasingly make use of a risk management approach. Besides forecasting failure probabilities and consequences, this approach requires decision tools to evaluate and compare different alternative strategies to reduce and control risk. In this paper we present a modeling approach that enables asset managers to quantify and prioritize options and generate multi-year action plans and strategies.

Related

Ageing Assets: Consume, Prolong, Replace

This paper will be discussed in an upcoming webinar on ageing asset management dd March 23.

The electrical contractor as the centre of competence

As systems such as electricity, ICT, and heating become more integrated, proper coordination between the different players in the building market is essential. Installers are in fact on-site experts and can assume an important role. As system integrators, they are not only responsible for installation, but they can also fulfil an advisory function. Yet many of the technologies are relatively new, unfamiliar to many installers, and will require substantial training. Provided this barrier can be overcome, ten opportunities, all ripe for a breakthrough, announce a bright future for the sector.

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