The Anonymous Widower

Gresham House Unveils 45-MW Battery Storage Purchase

The title of this post, is the same as that of this article on Renewables Now.

This is the introductory paragraph.

Gresham House Energy Storage Fund plc (LON:GRID) has acquired a 45-MW portfolio of battery storage systems in England, growing its operational fleet to 395 MW.

Gresham House are certainly growing.

As a Control Engineer and mathematical modeller, I certainly like what they are doing.

Modelling the cash-flow and earnings from all these batteries are is one of the sort of multi-variable problems, that I cut my teeth on, in early 1970s.

If I was starting out on my own now, as I did in 1972, Gresham House would be one of the companies I’d approach.

Their latest purchase is interesting in that it includes a 35 MW battery with a twelve year control to load balance for the National Grid.

There must also be a business model emerging for the developers of energy storage.

  • Design and build an energy storage system to satisfy a company or local area’s need.
  • Show it is working successfully for a period of time.
  • Add a nice lucrative contract if you can!

The whole setup is then sold to someone like Gresham House.

At present, Gresham House has a portfolio, which is all lithium-ion storage. I don’t think, it will be a long time before other types of storage are added.

February 2, 2021 Posted by | Energy, Energy Storage | , , | Leave a comment

A Thought On Covid-19

I am a Control Engineer, Mathematical Modeller and Statistician and have been following the data since the pandemic started.

Consider.

  • Systems like the pandemic want to get to an equilibrium. And preferably one where they are in control. The virus tries to infect more people, so they can pass it on.
  • But anybody, who is immune to the virus acts as a moderator does in a nuclear reactor, to slow the reaction down. So the more, who are immune in the population the better.
  • As of today, 2,713,563 have tested positive for the virus and sadly 75,431 have died. That means at least 2.6 million have had the virus and survived. Are these people now immune to the virus? If they are, can they be added to those who are vaccinated?
  • Also, how many people have had the virus and were not tested, but treated it like they might a cold? Are these safe from the virus, a second time around?
  • What about children, who seem to have lower susceptibility to the virus?
  • We can add in by the end of this week over a million, who have received the vaccine.
  • We are at the present time having about 350,000 positive tests in a week. If these people with positive tests isolate as they should, that will be breaking the transmission of a lot of carriers.
  • And then if the vaccine makers deliver two million a week and they are all used, that takes a lot of people out of the mix.
  • How many people are shielding or working from home and never giving the virus a chance to infect them? It must be a couple of million.

These are all big numbers, but most of them are on our side and not that of the virus.

I watched BBC News at six and Emma Vardy said that in Northern Ireland, the vaccine might be having a positive effect. I wouldn’t have expected that this early!

I am more optimistic, than I was before I started to write this post.

Could the combination of lockdown and increasing numbers of vaccinations cut the rate of transmission of the virus?

January 4, 2021 Posted by | Uncategorized | , , | 6 Comments

A Reason To Be Cheerful

I have a good reason to be cheerful.

When my wife died in 2007, I had the problem of what to do, with the money from the sale of her Porsche.

Peer-to-peer lending was just starting, so as a trained control engineer and mathematical modeller, I gave them a good check out!

I then put the money into an automatic peer-to-peer lender, where you deposit the money, forget it and the computer lends it out. Some of my family and friends, including my accountant were horrified.

Then came 2008 and the banking crisis. Like a Flower-Class corvette in the teeth of an Atlantic gale, it bounced safely through the crisis.

Since, then it has earned more than the stock market and grown.

And it repeated a similar safe passage through the Covid-19 crisis.

It does seem that there are always people with a good credit ratings that want to borrow money.

How much of the money borrowed in 2020 was for home improvements to cater for a home office or home schooling?

Conclusion

I blame my mother! I got my skill with and feel for numbers, from her genes and the tutoring she gave me,

She had won a scholarship to Dame Alice Owen’s School, but was unable to go to University, due to lack of funds, so she became a comptometer operator in the Account’s Department at Reeves, who used to make artist’s materials and were based just round the corner from where I now live.

That was probably, the only sort of job a mathematically bright young lady could do in the 1920s.

January 3, 2021 Posted by | Finance | , , , | Leave a comment

The Schoolgirl Who Helped To Win A War

The title of this post, is the same as a programme to be shown on the BBC News Channel, this weekend.

Seeing the trailers on the BBC this morning, I am reminded of my mother, who was my mathematical parent. The girl in the story is Hazel Hill, who was the daughter of Captain Frederick William Hill, who worked on armaments research.

My mother would be a few years older than Hazel and won a scholarship to one of the best girls schools in London at the time; Dame Alice Owen’s, which  was then in Islington.

I get the impression, that contrary to perceived opinion, that in the 1920s and 1930s, girls with aptitude were well-schooled in practical mathematics.

I’d be very interested to know, where Hazel Hill went to school.

I shall watch the programme.

July 10, 2020 Posted by | World | , , , , , | 1 Comment

Toilet Paper Calculator

Have you ever wondered how many toilet rolls you need to buy?

Those clever mathematicians at Omni, have now come up with a Toilet Paper Calculator.

It’s just one of their suite of Coronavirus Calculators.

I use their other calculators regularly.

This suite of calculators have a slightly humorous edge, that I find acceptable in these troubling times.

May 15, 2020 Posted by | Health, World | , , , | Leave a comment

My Past Is Worrying Me!

It must have been in the early 1970s, when I was acting as a mathematical-modelling consultant.

I was asked to do some modelling by a major drug company of the propagation of a virus through the UK population.

Their aim was to show how serious these pandemics could be and they wanted to get substantial grants from the Government to fund various lines of research.

With their data and the model I built, we were able to show how a dangerous pandemic could evolve.

But I never found out how successful they were in obtaining the money needed to start the research!

It does look like this pandemic could be the one that researchers at the company were predicting nearly fifty years ago.

March 13, 2020 Posted by | Computing, Health | , , , | 2 Comments

Batteries On Class 777 Trains

In this article on Railway Gazette, which is entitled Merseyrail Class 777 arrives in Liverpool, there is this sentence.

There is space under one vehicle to house a battery weighing up to 5 tonnes within the axleload limit.

This matter-of-fact sentence, draws me to the conclusion, that these trains have been designed from the start to allow future battery operation.

Batteries are not an add-on squeezed into a design with great difficulty.

Battery Capacity

Energy densities of 60 Wh/Kg or 135 Wh/litre are claimed by Swiss battery manufacturer; Leclanche.

This means that a five tonne battery would hold 300 kWh.

Note that Vivarail find space for 424 kWh in the two-car Class 230 train, I wrote about in Battery Class 230 Train Demonstration At Bo’ness And Kinneil Railway, so it would appear that Stadler aren’t being over ambitious.

Kinetic Energy Of A Full Class 777 Train

The weight of a full Class 777 train is calculated as follows.

  • Basic empty weight – 99 tonnes
  • Battery weight – 5 tonnes
  • 484 passengers at 80 Kg – 38.72 tonnes

Which gives a total weight of 143.72 tonnes.

Intriguingly, the weight of a current Class 507 train is 104.5 tonnes, which is 500 Kg more than an empty Class 777 train with a battery!

If these weights are correct, I suspect Stadler have used some very clever lightweight design techniques.

For various speeds, using Omni’s Kinetic Energy Calculator, this weight gives.

  • 30 mph – 3.6 kWh
  • 40 mph – 6.4 kWh
  • 50 mph – 10.0 kWh
  • 60 mph – 14.4 kWh
  • 70 mph – 19.5 kWh
  • 75 mph – 22.4 kWh

Note.

  1. The average speed between Bidston and Wrexham General stations on the Borderlands Line is under 30 mph
  2. The operating speed on the Wirral Line is 70 mph
  3. The operating speed on the Northern Line is 60 mph
  4. The maximum speed of the trains is 75 mph.

Every time I do these calculations, I’m surprised at how low the kinetic energy of a train seems to be.

How Small Is A Small Battery?

One battery doesn’t seem enough, for a train designed with all the ingenuity of a product with quality and precision, that is designed to out-perform all other trains.

This is another paragraph from the Railway Gazette article.

According to Merseytravel, ‘we want to be able to prove the concept that we could run beyond the third rail’. By storing recovered braking energy, the batteries would help to reduce power demand and the resulting greenhouse gas emissions. All of the Class 777s will be fitted with small batteries to allow independent movement around workshop and maintenance facilities.

I am not quite sure what this means.

It would seem strange to have two independent battery systems in one train.

I think it is more likely, that the smaller battery can be considered the primary battery of the train.

  • After all in the depot, it looks after the train’s power requirement.
  • Does it also handle all the regenerative braking energy?
  • Is it used as a secondary power supply, if say the power is low from the electrification?
  • Could it be used to move the train to the next station for passenger evacuation in the event of a power failure?

I wonder if the power system is a bit like the average battery-powered device like a lap-top computer, smart phone or hybrid car.

  • The electrification and the regenerative braking charges the battery.
  • The battery provides the traction and hotel power for the train.

When the five tonne battery is fitted, does the train’s control system move power between the two batteries to drive the train in the most efficient manner?

I’ll return to factors that define the size of the small battery.

The small battery must be big enough for these purposes.

  • Handling regenerative braking at the operating speed.
  • Recovering a full train to the next station.
  • Keeping a train’s systems running, during power supply problems.
  • Moving a train around a depot

As the lines leading to depots are electrified, the train can probably enter a depot with a battery fairly well-charged.

As the new Class 777 trains have a maximum operating speed of 75 mph, I would suspect that the small battery must be able to handle the regenerative braking from 75 mph, which my calculations show is 22.4 kWh with a full train. Let’s call it 30 kWh to have a reserve.

Using Leclanche’s figures, a 30 kWh battery would weigh 500 Kg and have a volume of just under a quarter of a cubic metre (0.222 cubic metre to be exact!)

I suspect the operation of the small battery through a station would be something like this.

  • As the train runs from the previous station, the power from the battery will be used by the train, to make sure that there is enough spare capacity in the battery to accommodate the predicted amount of energy generated by regenerative braking.
  • Under braking, the regenerative braking energy will be stored in the battery.
  • Not all of the kinetic energy of the train will be regenerated, as the process is typically around eighty percent efficient.
  • Whilst in the station, the train’s hotel services like air-conditioning, lights and doors, will be run by either the electrification if available or the battery.
  • When the train accelerates away, the train’s computer will use the optimal energy source.

The process will repeat, with the battery constantly being charged under braking and discharged under acceleration.

Lithium-ion batteries don’t like this cycling, so I wouldn’t be surprised to see dome other battery or even supercapacitors.

A Trip Between Liverpool and Wrexham Central in A Class 777 Train With A Battery

The train will arrive at Bidston station with 300 kWh in the battery, that has been charged on the loop line under the city.

I will assume that the train is cruising at 50 mph between the twelve stops along the twenty-seven and a half miles to Wrexham Central station.

At each of the twelve stops, the train will use regenerative braking, but it will lose perhaps twenty percent of the kinetic energy. This will be two kWh per stop or 24 kWh in total.

I usually assume that energy usage for hotel functions on the train are calculated using a figure of around three kWh per vehicle mile.

This gives an energy usage of 330 kWh.

But the Class 777 trains have been designed to be very electrically efficient and the train is equivalent in length to a three-car Class 507 train.

So perhaps a the calculation should assume three vehicles not four.

Various usage figures give.

  • 3 kWh per vehicle-mile – 247.5 kWh
  • 2.5 kWh per vehicle-mile – 206 kWh
  • 2 kWh per vehicle-mile – 165 kWh
  • 1.5 kWh per vehicle-mile – 123.8 kWh
  • 1 kWh per vehicle-mile – 82.5 kWh

Given that station losses between Bidston and Wrexham Central could be around 24 kWh, it looks like the following could be possible.

  1. With a consumption of 3 kWh per vehicle-mile, a Class 777 train could handle the route, but would need a charging station at Wrexham Central.
  2. If energy consumption on the train could be cut to 1.5 kWh per vehicle-mile, then a round trip would be possible.

It should also be noted that trains seem to do a very quick stop at Wrexham Central station of just a couple of minutes.

So if charging were to be introduced, there would need to be a longer stop of perhaps eight to ten minutes.

But the mathematics are telling me the following.

  • The Class 777 train has been designed to weigh the same empty as a current Class 507 train, despite carrying a five tonne battery.
  • If power consumption can be kept low, a Class 777 train with a battery can perform a round trip from Liverpool to Wrexham Central, without charging except on the electrified section of line between Liverpool and Bidston.
  • Extra stops would probably be possible, as each would consume about 2 kWh

I feel that these trains have been designed around Liverpool to Wrexham Central.

Conclusion

Wrexham Central here we come!

Other routes are possible.

  • Hunts Cross and Manchester Oxford Road – 27 miles
  • Ormskirk and Preston – 15 miles
  • Headbolt Lane and Skelmersdale – 6 miles
  • Ellesmere Port and Helsby – 5 miles
  • Kirkby and Wigan Wallgate – 12 miles

Chargers will not be needed at the far terminals.

February 4, 2020 Posted by | Transport | , , , , , , , , | 12 Comments

Could Modern Energy Systems Have A Secondary Role?

Close to where I live is a small heat and power system, that I wrote about in The Bunhill Energy Centre.

I first went over the centre during Open House.

Several of these modern systems are very good demonstrations of the principles of maths, physics and engineering.

So do these innovative energy systems do their bit in educating the next generation of scientists and engineers?

Some of the modern systems, that are in development like Highview Power’s energy storage using liquid air would be ideal for a secondary education role!

Most too, are very safe, as there are no dangerous processes or substances.

And in the next few years, there will be more systems all over the country and many in the hearts of towns and cities. Some schools, colleges and especially universities, will have their own innovative energy sources.

Liverpool University already has a system, which is described here.

January 16, 2020 Posted by | Energy Storage | , , , , , , | Leave a comment

The Mathematics Of Fast-Charging Battery Trains Using Third-Rail Electrification

In Vivarail Unveils Fast Charging System For Class 230 Battery Trains, I talked about how Vivarail are proposing to fast-charge their Class 230 trains.

  • The trains are fitted with special high-capacity third rail shoes.
  • Third-rail electrification is laid in stations.
  • The third rail is powered by a bank of bstteries, that are trickle-charged from the mains or perhaps even solar power.
  • When the train connects to the rail, the rail is made live and a fast transfer takes place between third-rail and train.

So how much electricity could be passed to a train during a stop?

The most powerful locomotive in the UK, that can use 750 VDC third-rail electrification is a Class 92 locomotive.

According to Wikipedia, it can produce a power output of 4 MW or 4,000 kW, when working on third-rail electrification.

This means, that in an hour, four thousand kWh will be transferred to the train using conventional third-rail electrification.

Or in a minute 66.7 kWh can be transferred.

In Vivarail’s system, because they are transferring energy between batteries, enormous currents can be passed.

To illustrate how batteries can can deliver enormous currents here’s a video of  a guy using two car batteries to weld things together.

These currents are possible because batteries have a low impedance and when the battery on the train is connected to the battery bank on the station, the two batteries will equalise their power.

If we take the example of the Class 92 locomotive and conventional electrification, this would be able to transfer 200 kWh in three minutes or 400 kWh in six minutes.

But I believe that battery-to-battery transfers could be at a much higher current

Thus in a typical one or two minute stop in a station, upwards of 200 kWh could be transferred to the train.

On this page of their web-site, Vivarail say this.

Due to the high currents required for the train Vivarail uses a carbon ceramic shoe able to withstand the heat generated in the process – without this shoe the charge time would make operational running unfeasible.

The devil is always in the details! From what I’ve seen and heard about the company, that would fit!

 

July 12, 2019 Posted by | Energy, Transport | , , , , , | 6 Comments

Mathematics Of A Stadler Flirt Akku Battery Train

In Stadler Receives First Flirt Akku Battery Train Order, I  quoted this from as that of this article in Railway Gazette International.

Schleswig-Holstein transport authority NAH.SH has selected Stadler to supply 55 Flirt Akku battery multiple-units to operate regional services and provide 30 years of maintenance.

This is a substantial order for a large number of trains and many years of maintenance, and would appear to be structured similarly to deals in East Anglia, Glasgow and Liverpool in the UK.

Does The Train Have A Central Power-Pack Car?

Is the Flirt Akku, similar to Greater Anglia’s Class 755 trains and other of the companies products, in that it has a central power-pack car?

This picture shows a Class 755 train at Norwich.

 

Note that this four-car train has four full-size cars and a shorter one, that doesn’t appear to have any doors or proper windows.

This is the power-pack car, which in these trains has the following properties.

  • The power-pack car is 6.69 metres long.
  • The power-pack car is identical in both the four-car and three-car versions of the Class 755 trains.
  • The four-car trains have four diesel engines.
  • The three-car trains have two diesel engines.

The number of engines possible, leads me to believe there are four slots for engines in the power-pack car.

Transport for Wales have ordered a number of Flirts, which are similar to those in use by Greater Anglia, but they are tri-mode trains, that can run on overhead 25 KVAC electrification, diesel or battery power.

I speculate that they have one diesel engine and three batteries in the four slots.

This is a picture of the Flirt Akku.

I have enlarged the image and it would appear that the trains do not have a central power-pack car, but they do seem to have a lot of electrical gubbins on the roof.

This video shows the Class 755 train being tested at Diss.

It looks to have a much smoother roof line.

Could this indicate that the batteries on the Akku are placed on the roof of the train, as there is certainly a lot of equipment up there?

 

 

 

June 22, 2019 Posted by | Transport | , , , , | 10 Comments