The Anonymous Widower

Hitachi And Eversholt Rail To Develop GWR Intercity Battery Hybrid Train – Offering Fuel Savings Of More Than 20%

The title of this post is the same as that of this press release from Hitachi.

The press release starts with these bullet points.

• Batteries replacing an engine to cut fuel usage and reduce carbon emissions
• First time a modern UK intercity train, in passenger service, will use alternative fuel
• Tri-mode train can improve air quality and reduce noise across South West route’s non-electrified stations

They follow these with this introductory paragraph.

In a UK-first, Hitachi Rail and Eversholt Rail have signed an exclusive agreement aimed at bringing battery power – and fuel savings of more than 20% – to the modern Great Western Railway Intercity Express Trains that carry passengers between Penzance and London.

After a couple more paragraphs, the press return returns to the Penzance theme.

GWR’s Intercity Express Train fleet currently calls at 15 non-electrified stations on its journey between Penzance and London, all of which could benefit from trains running on battery-only power.

The press release then sets out their aims.

The projected improvements in battery technology – particularly in power output and charge – create opportunities to replace incrementally more diesel engines on long distance trains. With the ambition to create a fully electric-battery intercity train – that can travel the full journey between London and Penzance – by the late 2040s, in line with the UK’s 2050 net zero emissions target.

Penzance gets another mention, but the late 2040s for a fully electric-battery intercity train between Penzance and London, is not an ambitious target.

Hitachi Intercity Tri-Mode Battery Train

Hitachi have called the train the Intercity Tri-Mode Battery Train and the specification is shown in this infographic.

Note that fuel & carbon savings of at least 20 % are claimed.

Penzance To London In A Class 802 Train

It would appear that Penzance and London has been chosen as the trial route.

These figures were obtained from Real Time Trains figures for the 1015 from Penzance on the 14th December 2020.

• Penzance to St. Erth – 5.65 miles – 8 mins – 42.4 mph – 1 mins stop
• St. Erth to Camborne – 7.2 miles – 10 mins – 43.2 mph – 1 mins stop
• Camborne to Redruth – 3.65 miles – 5 mins – 43.8 mph – 2 mins stop
• Redruth to Truro – 9 miles – 10 mins – 54 mph – 2 mins stop
• Truro to St. Austell  – 14.7 miles – 15 mins – 58.8 mph – 1 mins stop
• St. Austell to Par – 4.5 miles – 6 mins – 45 mph – 1 mins stop
• Par to Bodmin Parkway – 8 miles – 11 mins – 43.6 mph – 1 mins stop
• Bodmin Parkway to Liskeard – 9.2 miles – 12 mins – 46 mph – 1 mins stop
• Liskeard to Plymouth – 17.8 miles – 25 mins – 42.7 mph – 9 mins stop
• Plymouth to Totnes – 23.1 miles – 25 mins – 55.4 mph – 1 mins stop
• Totnes to Newton Abbot – 8.8 miles – 9 mins – 59.3 mph – 2 mins stop
• Newton Abbot to Exeter St. Davids – 20.2 miles – 18 mins – 71.3 mph – 2 mins stop
• Exeter St. Davids to Tiverton Parkway – 16.5 miles – 14 mins – 70.7 mph – 1 mins stop
• Tiverton Parkway to Taunton – 14.2 miles – 11 mins – 77.4 mph – 2 mins stop
• Taunton to Reading – 106.7 miles – 76 mins – 84.2 mph – 5 mins stop
• Reading to Paddington – 36 miles – 25 mins – 86.4 mph

The route can be broken neatly into four very different sections.

• Penzance and Plymouth – 79.5 miles – 112 mins – 42.5 mph – 75 mph operating speed
• Plymouth and Exeter St. Davids – 52 miles – 57 mins – 54.7 mph – 100 mph operating speed
• Exeter St. Davids and Newbury – 120.4 miles – 95 mins – 76 mph – 100 mph operating speed
• Newbury and Paddington – 53 miles – 36 mins – 88.3 mph – 100-125 mph operating speed

Note.

1. The speed builds up gradually as the journey progresses.
2. Only between Newbury and Paddington is electrified.

How does Penzance and Paddington stand up as a trial route?

• Penzance and Plymouth has eight intermediate stops about every nine-ten miles.
• The nine minute stop at Plymouth, is long enough to charge the batteries, should that be incorporated in the trial.
• The Cornish Main Line is generally double track, with an operating speed of 75 mph.
• Plymouth and Exeter includes the running by the sea, through Dawlish.
• Exeter could be given an extended stop to charge the batteries.
• Exeter and Newbury is a faster run and the batteries may help with performance.
• The Reading and Taunton Line has an operating speed of 110 mph.
• Remember the trains are designed for 140 mph and they achieve nothing like that on diesel.
• At each of the fifteen stops, the performance, noise and customer reaction can be evaluated. Strange, but my experience of battery trains, says that they are very much quieter than similar electric trains.

The route has a good selection of the types of routes, that Great Western Railway has in its network.

It would appear to be a good route to sort out the good and bad points of the train.

I have a few thoughts.

Possible Destinations For A Intercity Tri-Mode Battery Train

Currently, the following routes are run or are planned to be run by Hitachi’s Class 800, 802, 805 and 810 trains, where most of the route is electrified and sections do not have any electrification.

• GWR – Paddington and Bedwyn – 13.3 miles
• GWR – Paddington and Bristol Temple Meads- 24.5 miles
• GWR – Paddington and Cheltenham – 43.3 miles
• GWR – Paddington and Great Malvern – 76 miles
• GWR – Paddington and Oxford – 10.4 miles
• GWR – Paddington and Penzance – 252 miles
• GWR – Paddington and Swansea – 45.7 miles
• Hull Trains – Kings Cross and Hull – 36 miles
• LNER – Kings Cross and Harrogate – 18.5 miles
• LNER – Kings Cross and Huddersfield – 17 miles
• LNER – Kings Cross and Hull – 36 miles
• LNER – Kings Cross and Lincoln – 16.5 miles
• LNER – Kings Cross and Middlesbrough – 21 miles

Note.

1. The distance is the length of line on the route without electrification.
2. Five of these routes are under twenty miles
3. Many of these routes have very few stops on the section without electrification.

I suspect that GWR and LNER have plans for other destinations.

What Is The Kinetic Energy Of A Five-Car Class 802 Train At Various Speeds?

I will do my standard calculation.

• Empty train weight – 243 tonnes (Wikipedia for Class 800 train!)
• Passenger weight – 302 x 90 Kg (Includes baggage, bikes and buggies!)
• Train weight – 270.18 tonnes

Using Omni’s Kinetic Energy Calculator, the kinetic energy at various speeds are.

• 60 mph – 27 kWh
• 75 mph – 42 kWh
• 80 mph – 48 kWh
• 90 mph – 61 kWh
• 100 mph – 75 kWh
• 110 mph – 91 kWh
• 125 mph – 117 kWh – Normal cruise on electrified lines.
• 140 mph – 147 kWh – Maximum cruise on electrified lines.

A battery must be large enough to capture this kinetic energy, which will be generated, when the train stops.

Acceleration And Deceleration Of A Five-Car Class 802 Train

The first Intercity Tri-Mode Battery Trains will be conversions of Class 802 trains.

This page on the Eversholt Rail web site, has a data sheet for a Class 802 train.

The data sheet shows the following for a five-car Class 802 train.

• It can accelerate to 120 kph/75 mph in 100 seconds in electric mode.
• It can accelerate to 160 kph/100 mph in 160 seconds in electric mode.
• It can accelerate to 120 kph/75 mph in 140 seconds in diesel mode.
• It can decelerate from 120 kph/75 mph in 50 seconds in electric mode.
• It can decelerate from 160 kph/100 mph in 90 seconds in electric mode.

Note.

1. 75 mph is the operating speed of the Cornish Main Line and possibly the Highland Main Line.
2. 100 mph is the operating speed for a lot of routes in the UK.
3. It would appear that trains accelerate to 75 mph forty second faster in electric mode, compared to diesel mode.
4. In diesel mode acceleration slows markedly once 100 kph is attained.

Can we assume that performance in battery mode, will be the same as in electric mode? I will assume that this is valid.

Battery Use In A Station Stop

Suppose the train is travelling at 75 mph with a full load of passengers and makes a station stop, without the use of the diesel engines.

• If the train is decelerating from 75 mph, there must be space for 42 kWh in the battery.
• Because regenerative braking is not 100 % efficient, only perhaps 80 % would be stored in the battery. This is 33.6 kWh.
• To accelerate the train to 75 mph, the battery must supply 42 kWh, as diesel power will not be used for this purpose.
• The train will take 50 seconds to decelerate, 100 seconds to accelerate and perhaps 60 seconds in the station or 210 seconds in total.
• Let’s say the battery will need to supply 2 kWh per minute per car for hotel power, that will be 35 kWh for the 210 seconds.

Adding and subtracting inputs and outputs to the battery gives this equation 33.6 – 35 – 42 = -43.4 kWh

The energy in the battery has been reduced by 43.4 kWh, at each 75 mph stop.

Repeating the calculation for a 100 mph stop, which takes 310 seconds, gives an equation of 60 -51.7 – 75 = -66.7 kWh.

Note that in this calculation, I have assumed that the efficiency of regenerative braking is 80 %. These are a selection of figures.

• For 60 % efficiency, the stops would cost 51.8 kWh from 75 mph and 81.7 kWh from 100 mph.
• For 80 % efficiency, the stops would cost 43.4 kWh from 75 mph and 66.7 kWh from 100 mph.
• For 90 % efficiency, the stops would cost 39.2 kWh from 75 mph and 59.2 kWh from 100 mph.

So it is important to raise the efficiency of regenerative braking to as near to 100 % as possible.

It should also be noted that with an 80 % efficiency of regenerative braking, hotel power has an effect.

• With 1 kWh per minute per car, the stops would cost 25.9 kWh from 75 mph and 40.8 kWh from 100 mph.
• With 2 kWh per minute per car, the stops would cost 43.4 kWh from 75 mph and 66.7 kWh from 100 mph.
• With 3 kWh per minute per car, the stops would cost 60.9 kWh from 75 mph and 92.6 kWh from 100 mph.

It is important to reduce the hotel power of the train, as low as possible.

With a 90 % regeneration efficiency and hotel power of 1 kWh per car per minute, the figures are 21.7 kWh from 75 mph and 33.3 kWh from 100 mph.

London Paddington And Penzance By Intercity Tri-Mode Battery Train

Listing the stops between London Paddington and Penzance and their speeds gives the following.

• St. Erth – 75 mph
• Camborne – 75 mph
• Redruth – 75 mph
• Truro – 75 mph
• St. Austell – 75 mph
• Par – 75 mph
• Bodmin Parkway – 75 mph
• Liskeard – 75 mph
• Plymouth – 75 mph
• Totnes – 100 mph
• Newton Abbot – 100 mph
• Exeter St. Davids – 100 mph
• Tiverton Parkway – 100 mph
• Taunton – 100 mph
• Reading – Electrified

This is nine stops from 75 mph, five from 100 mph and one where the electrification is used.

• Each 75 mph stop needs 43.4 kWh from the battery.
• Each 100 mph stop needs 66.7 kWh from the battery.

To achieve Hitachi’s aim of low noise and pollution-free station stops between London Paddington and Penzance will need 724.1 kWh of power from the battery.

With 80 % regeneration efficiency and hotel power of 2 kWh per minute per car gives a figure of 724.1 kWh.

With 90 % regeneration efficiency and hotel power of 1 kWh per minute per car gives a figure of 361.8 kWh.

The battery must also have sufficient capacity to handle the regenerative braking. I would suspect that provision will be made for a stop from 125 mph, which is 117 kWh.

So will the battery for the route be somewhere between 500 and 1000 kWh?

Note that each of the three MTU 12V 1600 diesel engines, fitted to a Class 800 train, weigh around two tonnes and Tesla claim an energy density of 250 Wh/Kg for their batteries.

This would mean a battery the weight of one of the diesel engines would have a capacity of 500 kWh.

A train with a full 500 kWh battery at Newbury could arrive in Penzance with some juice in the battery, if regenerative braking could be efficient and the demands of the train to run internal systems were at a low level.

Hitachi’s Increasing Efficiency Of Class 80x Trains

The next variant of the Class 80x trains to come into service, should be the Class 803 trains for East Coast Trains.

• These trains will be all-electric like LNER’s Class 801 trains.
• They are designed for a four-hour limited-stop service between London Kings Cross and Edinburgh.
• They will be one-class and average single fares will be £25,

This sentence from Wikipedia, describes a big difference between Class 803 and Class 801 trains.

Unlike the Class 801, another non-bi-mode AT300 variant which despite being designed only for electrified routes carries a diesel engine per unit for emergency use, the new units will not be fitted with any, and so would not be able to propel themselves in the event of a power failure. They will however be fitted with batteries to enable the train’s on-board services to be maintained, in case the primary electrical supplies would face a failure.

I wouldn’t be surprised to find out that the Class 803 trains have been put on a diet to increase their acceleration to meet the demanding schedule, which has been promised by East Coast Trains.

Hitachi has also given out clues to other efficiency improvements.

• Class 807 trains for Avanti West Coast, will have no diesel engines or batteries.
• Class 810 trains for East Midlands Railway will have a revised nose and different headlights. Is this for better aerodynamics?
• Class 810 trains, also have slots for four diesel engines. I can’t see why they would need all this power on the relatively-flat Midland Main Line. Will two of the slots be used by batteries to reduce fuel consumption and/or increase efficiency?

Hitachi are only doing, what all good engineers would do.

Low-Carbon Between Plymouth and Penzance

In How Much Power Is Needed To Run A Train At 125 mph?, I estimated that an all-electric Class 801 train needs around 3.42 kWh per vehicle mile to maintain 125 mph.

It will need less power to maintain the 75 mph of the Cornish Main Line. I would suspect that as air resistance is based on the square of the speed, that the energy consumption of the Class 802 train could be something under 2 kWh per vehicle. Or even less!

The Cornish Main Line is 79.5 miles between Plymouth and Penzance, but the Intercity Tri-Mode Battery Train, will not be on diesel all the way.

• At each station stop deceleration and acceleration, the train will not be using diesel. This could take a mile away for each station.
• All braking will be regenerative to the battery.

I suspect that by using the gradients on the route to advantage and by using diesel in selected areas, that a good driver or a well-written driver assistance system giving advice could safely navigate an Intercity Tri-Mode Battery Train all the way to Penzance on a minimum amount of diesel.

It’s not as if the train will be stranded, as they would have two onboard diesel engines.

I have a suspicion, that with a top-up at Plymouth, if Hitachi can raise efficiencies to a maximum and power consumption to a minimum, that on one battery, the train might be able to run between Plymouth and Penzance for much of the way, without using diesel.

The question also has to be asked, as to what would be the performance of the train with two diesel engines replaced by batteries?

I suspect this is something else to be determined in the trial.

Will Hitachi’s Intercity Tri-Mode Battery Train And Regional Battery Train Have The Same Battery Packs?

The specification of Hitachi’s closely-related Regional Battery Train is described in this Hitachi infographic.

The Regional Battery Train is stated to have a battery range of 90 km/56 miles at 162 kph/100 mph.

Operating speed and battery range have not been disclosed yet for the Intercity Tri-Mode Battery Train. I await them with great interest.

I would expect that it is likely, that Hitachi’s two battery trains and others that follow, will use identical battery packs for ease of manufacture, services and operation.

In their press release, which announced the Battery Regional Train, Hitachi said this.

Hitachi has identified its fleets of 275 trains as potential early recipients of the batteries for use in the UK, as well as installing them on new metro and intercity trains that will be needed in the coming years to replace ageing diesel fleets.

Battery trains produce no greenhouse gases, air pollution and are a far quieter, offering passengers cleaner air in stations, less noise disruption and a carbon-free way to travel. Installing batteries on to existing fleets can also extend their range and allow passengers to reach stations on non-electrified branch lines without having to change train.

They didn’t exactly say all battery packs will be the same, but they were close to it, by saying that they can already be fitted to 275 trains. I would read those paragraphs to say, that a series of trains would use the same technology for different purposes.

What Will Be The Battery Range Of A Hitachi Intercity Tri-Mode Battery Train?

This page on the Eversholt Rail web site, has a data sheet for a Class 802 train, which says that a five-car Class 802 train has  an operating speed of 110 mph on diesel power.

According to Wikipedia and other sources, a Class 802 train has three diesel engines.

If the Regional Battery Train has replaced three diesel engines with battery packs in a five-car train like a Class 802 train to get the 90 km/56 mile range, would this mean?

• Replacing one diesel engine with a battery pack, give a range of thirty kilometres or about nineteen miles.
• Replacing two diesel engines with battery packs double the range to sixty kilometres or thirty-eight miles.

It looks like a Hitachi Intercity Tri-Mode Battery Train with one of the same battery-packs should easily reach several of the destinations in my list.

But they would need charging before return or some assistance from the two remaining diesel engines.

I talk about charging the Intercity Tri-Mode Battery Train in Charging The Batteries On An Intercity Tri-Mode Battery Train.

Conclusion

It sounds like a worthwhile train to me and I await the results of the trial with interest.

 

 

 

 

 

November 26, 2021 - Posted by AnonW | Transport/Travel | Battery-Electric Trains, Class 802 Train, Cornish Main Line, Great Western Railway, Hitachi Intercity Tri-Mode Battery Train, Hitachi Regional Battery Train, LNER, Penzance Station, Vivarail Fast Charge