Co2 emissions.. Steam or diesel best?

Hello everyone, I'm new here.

I have recently created a discussion on the giffgaff community about steam locomotives and their fuel following a chat with a friend who's not sure about being involved with them because how he thinks they might impact the environment. A lot of people were saying on there that the combined emissions of heritage lines in the UK wouldn't register on the scale of collective global emissions. Here's a link to it (I think you can view it without being with giffgaff)

**LINK**

My friend suggested that maybe having the body of a steam locomotive but with high quality sound effects and an electric or diesel engine (talking full size standard gauge here) would be cleaner. But would it actually be? Is diesel any different from steam in terms of carbon footprint? And electricity is still mainly from coal fired power stations.

This discussion has been going around heritage lines because of uncertainty on the future government decisions on access to coal from UK mines and the issues of getting it imported if it comes to it. I hope steam railways will keep their access to coal and long live steam!

Actually the percentage that coal generates is single-digit.

**LINK**

The steam engine's atrocious efficiency make it a much worse prospect than even the dirtiest diesel. They're yesterday's technology for lots of good reasons.

IC engines aren't far behind them either

If people are concerned about the emissions from "model" steam locomotives which are used on a very infrequent basis, perhaps they should spend more time worrying about their own personal CO2 emissions and hold their breath !!

Particularly those most verciferous.

I find the people making the most noise about CO2 emissions from models, modern cars, etc happily fly to vacation destinations around the world, the jets producing thousands of litres of CO2 every trip.

(and conveniently ignore 20 million two stroke small motorbike engines in Asia running all day spewing CO2 and unburned hydrocarbons, gigantic coke and steel works in Asia spewing thousands of tons of CO2 yearly, etc.)

I was more meaning full scale standard gauge locomotives.

Thank you so much for that informed correction!

There is not really any advantage of coal in comparison with electric.

Near 50% of electricity is currently (on average) generated by low carbon technology (nuclear, wind, solar, biomas, hydro, imports)

Most of the fossil fuel generation is with closed circuit gas turbines and these are greater in efficiency (over coal burning) by something close to 50%. It also produces only about half the carbon dioxide emissions, compared to coal generation (per unit produced).

Perhaps you should study the likes of:

**LINK**

or others of similar ilk. Plenty of information to be gleaned (if one is understanding the different statistics of electricity generation).

Steam lorries are exempt from the London LEZ.

The main problem is over population of the planet, luckily nature may sort this out when antibiotics stop working and a plague rips through the population. Nature will look after us or maybe god will sort it out. Zager and Evans made a nice song but it’s beginning to be quite prophetic.

Mike

A couple of years ago I went on the Mount Washington cog railway. We were told the steam locomotives had been changed form coal to green diesel. I think one of the owners has something to do with green diesel production. Any way they used two ton of coal for the whole trip, now they use five gallons of diesel. Figure the CO2 change not only for the journey but also the delivery of fuel to the site.

My main concern is the preservation of UK heritage railways and them being able to run. I felt quite sad that my friend was deterred from them because of the coal burning. Was hoping to find a few facts that agree that running steam engines for fun/leisure/heritage isn't that big of a worry to do with the environment just because they use coal compared with other things like aeroplane flights/big companies/cars and road vehicles

And mainly about standard gauge railways....

I am a member of a model engineers club and do have a 5" gauge loco so I do have a valid reason for being a member, not just random research haha

(and narrow gauge lines too of course)

Like people have said, the emissions of live steam models is very tiny and wouldn't really be worth worrying about at all in the grand scheme of things

The definitive answer to this question will be elusive and will require first the agreement of a standard of comparison between the diesel and the coal powered loco. Probably the most relevant method is to calculate or measure the g/kWh emitted of the individual pollutants (CO, CO2, particulates, NOx SOx etc). Even assesment of the particulates will be controversial to agree on because those emitted by the diesel will be mainly in the micro size range that are considered hazardous to health but those from the steam loco will be in the main much larger and considered a nuisance rather than a direct hazard when the loco is being fired correctly and worked hard. I doubt but am prepared to be corrected that there are any actual emissions figures measured from a standard gauge steam loco. I would respectfully suggest if this is all you have to argue about you both consider getting out more (on your bikes of course).

HowardT if you think you can really replace the energy in 2 tons of coal with that in 5 gallons of diesel I think you are in la la land! Diesel is a fuel of high energy density but not that high, someone is pulling your leg. A standard gauge 060 loco pulling 5 mk1 coaches (about 170 tonne) over a line with moderate gradients will travel around 60 miles on 2 tons of coal at an average speed of around 17mph (about 3 1/2 hours non stop) evaporating the volume of the boiler around 8 times. If you can replicate that with 5 gallons of diesel I think you have just solved the energy and climate crisis at a stroke!

Paul.

Biomass is NOT low carbon, The reports say the Drax power station is now carbon neutral because it runs on biomass. Unfortunatly the biomass is wood pellets at least some of which is produced in america. The CO2 emitted in harvesting the wood, drying it or transporting it (ships burnig dirty bunker oil) is not counted. And biomass produces more CO2 per Watt than gas.

Robert G8RPI.

Perhaps you should have a look at the link. Not particularly low, but 87kg/s for 2 1/2 GW equates to 360kg/s of emissions (according to the link) for10GW, which is what CCGTis currently running - producing 1100kg/s of CO2.

I’m not a fan of even cutting down trees for this ‘phoney’ biomass generation (for subsidies) but it is NOT classed as high CO2 by those that should know.

I also do not count pumped hydro as zero carbon emissions, as they do. I consider it as derived from the highest carbon generation at the time of pumping. Clearly gas or coal generation in my book!

The issue is 'net CO2'. Biomass recycles 'current' CO2, if I can put it that way. Fossil fuels release carbon accumulated over hundreds of millions of year giving an unnatural peak in CO2 due to the extreme rate of use.

Reforesting parts of the UK historically covered in deciduous woodland and harvesting it with larger timbers used for construction, furniture and fuel (locally to production, in log sections not pellets), putting trees back into hedgerows and stopping cutting them down without replanting, letting heathland, moorland and low grade agricultural land regenerate to woodland where that was their history will all help restore the balance. Trees, especially coppiced woodland, strip CO2 at a tremendous rate and provide other benefits in terms of moderating air temperature and the rate of rainwater run-off.

Sadly in much of the UK and other countries the number of trees continues to reduce.

This alone will not provide for our energy demands so other initiatives will be required, but I do wonder if putting photo voltaic panels on agricutural land is the right answer, the roofs of schools, barns, industrial buildings and similar large buildings seems more sustainable to my mind.

Thanks so much for everyone's thoughtful responses