SCR or EGR, how hard can it be?

Somewhat surprised I learn that there is still some discussion about weather SCR or EGR is the better choice. When I moved from research to become environmental director at Volvo Bus Corporation, soon two years ago, we just finished the final technology evaluation of the catalytic aftertreatment system that Volvo uses. There were undoubtedly major advantages for the fuel consumption also when the AdBlue use was compensated for, when compared to the most recent EGR technology.

The cost efficiency works out as several percent benefit on the bottom line for the operators. The exact numbers depends, amongst others, on the route and on the driving style. It reaches between 3 and 9% for most customers, when the AdBlue cost is compensated for.

In a recent article in the Danish magazine “Danske Busvognmaend”; Isue 3 March 2008, the last years experiences are summarised (in Danish however). http://www.db-dk.dk/ (the article is not available on the homepage)

The new interesting information in this article is that the same engine in the same installation is compared with the two technologies.

The Magazine summarises the properties:

Catalytic exhaust treatment Selective Catalytic Reduction (SCR)	Exhaust Gas Recirculation technology (EGR)
Fuel consumption decrease relative Euro III 10% better than EGR, while ~5% AdBlue is consumed	Fuel consumption increase relative Euro III
Longer oil change intervals	No extra installation
Less technical “stress” because of lower temperature	No concern about filling AdBlue
Higher power possible
Less complicated engine design

 

Or as one manufacturer said: “Just add diesel”

“… plenty of it…” I remarked.

Political ambivalence about bio fuels

If you are not already about to buy new buses for your local city transports, imagine yourself being in the situation of having to invest in new buses in a near future. As public transport authority or service provider you have been asked to provide environmentally friendly transports, but which?

 Volvo 7700 Biogas bus

You know that EU proposal for public procurement strongly promote cost efficient solutions with low fuel consumption. On the other hand the energy directive mainly focus on replacing coal fired electrical power plants in your region. And, there is not much help to gain from the lists of numerous fuels that can be considered. What is the implication for you?

The local farmers can provide some local production of biodiesel with reasonable efficiency but for securing the needed capacity and broadening the raw material base you know that a recent UN reports stress the importance of securing a strategy that will not sacrifice the food production and we don’t get much guidance what this will mean for different fuels.

Production of biogas is a safe choice since it combines waste management (sewage, manure and other wet wastes) with fuel production. The production capacity will hopefully be sufficient for fuelling the local city buses but not much more. Is this the preferred choice?

At the same time the EU leaders hesitate as for long term commitments:

http://news.bbc.co.uk/2/hi/europe/7293436.stm

I have said it before and I say it again: We need long term (~20 years) political commitments to secure sustainable fuel production, vehicles and infra structure. Industrial investment decisions in the vehicle sector have a time constant of 4-5 elections!

For biogas the most recent introduction is our new 9 litre engines:

http://www.volvo.com/bus/global/en-gb/products/City+buses/Complete+buses/Volvo+7700/Introduction_new.htm?TAB=4

Rapeseed oil to the air

Last Thursday the Swedish bus & coach operator Flygbussarna released the news that they will introduce rape seed oil (RME) for their buses.The news became relatively big on the Swedish national radio during last Friday.

http://www.peopletravel.se/NewsItem.aspx?page=3132&&lang=EN  (Sorry for the Swedish)

I have previously stressed the importance of considering the full product cycle when introducing biofuels. It is therefore particularly positive to learn that Flygbussarna put specific demands on the well-to-wheel performance of the fuel. Starting with Arlanda airport in Stockholm, Flygbussarna commit to gradually increasing the use to all buses travelling 7 airports in Sweden.

I was invited to an information event Friday lunch at Universeum in Göteborg -a miniature of the ecosystem of the world:

http://www.universeum.se/index.php?lang=en

Sten Ljungström, Associated Professor at Chalmers University and at Universeum, gave an excellent explanation of the origin of the global warming. Actually, this was the first time I have heard someone explain the relatively complicated matter in a way, easy to understand. I was quite surprised when I learned that Sten was invited as speaker (together with me). The organisers did obviously not know that we have been doing research on catalysis together for many years. We are still good friends.

It’s a small world.

Sustainable fuels is not the most important

Yesterday, Maud Olofsson, Swedens Minister for Enterprises and Energy, opened the Swedish National Energy Convention. She took the opportunity to sumarise her recent visit to the Wirec Conference, in US capital Washington DC: “There was a general agreement, we don’t need more reports about global warming, its time for action”.

An extensive part of the over 30 minute speech brought attention to the transport sector. Minding that Sweden is one of few countries in the world using almost no fossil sources for power generation, the transports are next in line. The minister has a vision where Sweden goes in the fore front, exemplifying the best practice. Alternative fuels such as Ethanol, biogas and biodiesel were mentioned as excellent opportunities for Swedish industry.

But little guidance were given as for which long term rout to decide for. “… its time for action…”. After all, the life time of a bus is often 15-25 years. The operators need solid commitments.

 Jan-Eric Sundgren

Jan-Eric Sundgren,  AB Volvo Senior Vice President for Environment and Governmental Affairs, remarked that even if the recent European Energy directive is on the right way, the time frame is too short. Investments made in the vehicle industry have a time constant, for new technology, of much more than the 12 years that remain to the targets set for 2020. And, the indicated direction to 2020 is not sufficiently solid. Besides, Sweden lags behind when it comes to support for R&D, Sweden is far from the 1% goal.

I would like to ad that the discrepancy in targets topped by the goal for 49% renewable energy in Sweden by 2020, and with 9% for the more fossil depending countries in Europe, give diverging priorities for the transportation sector. Most countries should focus on replacing coal fired power plant by biomass, while Sweden for example needs to cut deep in to the transportation sector. The Swedish market is certainly not big enough for leading the way in the public transport sector and the disharmonised development will drive extensive costs for the odd local fuels.

I had the opportunity to talk at one of the parallel sessions in the afternoon. To lower the climate impact of person transports we need a major shift in priorities. Its all really simple. The transports should be prioritised in order of cost efficiency for environmental impact. The most urgent measures then become:

1, Give the public transports priority. Buses, as the most environmental friendly mean of public transports come out with the highest priority; for infrastructure, for traffic lights, etc.

2, Make it easier to access the buses, by car, by bike and for pedestrians.

3, Support energy efficient public transports such as hybrids. There is an urgent need to reach critical volumes in production and initial support will make a huge difference to the pace of change.

4, Give long term direction for if and which alternative fuels society will support. Solid commitments for 20-30 years are needed to gain trust.

Mind that, even if important, switching to sustainable fuel has least impact and is most costly of the four measures above.

Common Procurement meeting in Nantes

The European Compro project arranged a workshop for environmental friendly technology the 4th of March. The Compro project aims at supporting the development of environmentally friendly technologies, by establishing common procurement criteria.

Europe suffers, since long, from diverging demands on environmental products. Each demand is often well justified by a high environmental ambition.But, the total picture counteracts the ambition of improvement. The large number of special requests for not legislated emission performance, for special fuels, for local test cycle data etc. drives cost and it becomes impossible to get a critical mass for new technologies.

The solution is a technology neutral approach.It will thus be possible to predict which technologies that will be favoured in the longer time perspective it also gives a guarantee for cost efficiency.

Or let me put it like this. Which is better for the environment, at same cost: One fuel cell demonstrator buses running with average 30 persons during 3 years or ten new high capacity BRT buses serving in average 400 persons during 10 years? The answer is not obvious in the long time perspective where the enabler of potential new technology is needed.

But if I ask: Which is better? 223 different specific and different demands from European cities and demonstration projects or a massive increase of the amount of public transports the answer is simple, when the limited resources are considered. I support the idea of common procurement criteria as a way weed out the overlaps and to support coordination of common demands.

By the way, I have previously been complaining about the slow development of bus infrastructure in Europe. I may have to reconsider. Nantes demonstrates an excellent show case how pedestrians, bikes, cars, trams, ferry, trains and buses can be integrated smoothly. The Nantes BRT bus stops have been equipped with modern design that attracts passengers from the less environmentally friendly modes of transports.

Cylindrical bus stop in front of the “Chatau de

Ducs de Bretagne” in Nantes

After the workshop I went jogging along L’Erdre. There was a frisk breeze from the Atlantic sea. The people living in Nantes are very sporty. There were hundreds of joggers running along the river. Many of which kept an impressive tempo, or if they were training for the Olympics. I don’t know. The most peculiar thing was a little passenger ferry connecting L’Erdre with Loire via a 2 km tunnel.