India is rolling out trains with solar-powered coaches | Hacker News Reader

India is rolling out trains with solar-powered coaches

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79 pointsprostoalex53 comments

Best case, that much solar generates about 38 horsepower for about 5 hours per day. The engine generates about 4000 horsepower. I would be astounded if this lowered fuel usage by 1% after you count the added weight of the batteries and electronics or if it lowered costs by anywhere near 1% due to the added maintenance issues.

I think they seem to say that each compartment has it's own diesel generator. They don't seem to use the train engine for that.

Unlikely. I've never seen a rail coach with its own power, other than perhaps some batteries for backup emergency lighting.

Coaches draw power from the locomotive which already has a huge generator to power the traction motors.

That's not how modern trains generally work although it's possible that's how India's trains still work.

Usually there's a HEP (head-end power) generator on the locomotive and the rest of the coaches are just plugged into that/each other to distribute the power down the train. Most regions have standard connectors/voltages and such to make this pretty seamless.

This is for engine power but for other electrical usage inside the train.

Completely agree. They can be lucky if these panels power on board electricity and air conditioning (in new trains that have those) but that's about it.

A diesel locomotive and full trainsets is hundreds of tons heavy. You can't propel these with a handful of solar panels on top.

The panels will "power the lights, fans, and information display systems inside passenger coaches", which are currently powered by separate diesel engines, thus already incurring fuel & maintenance costs.

I just wish those solar panels don't get stolen. That's a major problem with major valuable government installations here. People have stolen coal, road construction material etc. Although this seems impossible with the solar panels as they have been attached tightly. But with internal help from government employees, it is not.

Coal, Road construction materials, switches, panels, lights,etc have immediate economic value, even in small quantities.

Solar Panels are a whole different game altogether. IMO theft is not such a big issue.

The bigger issue is power loss due to lack of cleaning, battery life reduction due to lack of maintenance, etc.

It's not just the panels, you have batteries, converters, etc that need good maintenance to get a consistent ROI. However, the unit cost of power from diesel is definitely much higher than that from the grid and solar panels have a pretty good ROI when compared to power from the grid.

I personally think this transition would have been more efficient if all engines are switched to the electric ones and electricity is provided from stationary solar power plants in the higher radiation regions. It will be more efficient and easy to maintain.

What so you mean by electric engines? Electrification of rail lines is a pretty expensive undertaking, although I will admit I'm not certain of the specifics. I'm guessing that it makes sense only for shorter distances, which is why local trains/metros do use electrified tracks.

This seems like a good step in reducing costs of long distance train travel. Not to mention: a lot of experience would be gained in installing and operating solar panels, which could then be used elsewhere.

Thinking in terms of long-term ROI is a better way to evaluate electrification of Rail lines, rather than the upfront cost. Govt's can bear such a cost and ROI on electrified rail lines should be pretty damn good.

It's not impossible. Also, there is a scope of making the whole system carbon neutral.

I always wondered why electrification of major rail lines is not accompanied by updating and implementation of a more modern and efficient power grip. The two can parallel each other due to right of ways and while you cannot directly power your train from those high voltage lines the substations along the way make for good connection points

I don't know about other countries, but in India, the Rail power grid is completely isolated from the consumer grid.

Also, from a technical standpoint, especially for renewable energy systems, it's best to have isolated pockets of energy generation and consumption rather than a country wide grid.

Due to the intermittent nature of power available from renewable energy sources, it's best to have micro grids and micro storage systems.

In case of railway lines, the load on the network can be calculated to a very good accuracy, unlike the consumer grid. Hypothetically, this can mean that the rail grid can be isolated and be managed at a very high efficiency level.

Electrification becomes economical wherever there is a lot of _traffic_, independent of the length of the lines. The Transssibirian railway is electrified, and it hosts the longest passenger train-car (Moscow-Pyongyang, 9 days).

True. A Regional battery system, with isolated grids and solar panels should be a viable system, especially since the load is known almost perfectly before hand.

Think about all the lead poisoning.

Li-Ion batteries are much safer for the environment. Most modern battery systems use such types.

I think you'd find that people would start tapping the tracks for the power.

You mean from the 25 kV lines?

It's a nice idea, but I wonder whether they should maybe spend their money on electrifying their network, at least in the cities. The fuel used to power lights, screens, etc in the coaches must be a small fraction of the energy required to move the train.

Do trains have the same mechanisms cars use to generate electricity?

I don't know about Indian trains, but in the U.S. most locomotives are diesel-electric, meaning that they use a diesel powered electric generator coupled to electric motors. Definitely plenty of electricity.

I think shard asked about regenerative breaking.

*braking

what a nice paradoxical typo

I should have thought the disparity in cost between solar panels on roofs of trains vs electrifying millions of miles of track is gigantic?

Solar panels are also a lot cheaper than they used to be.

That's true. Power to the fans and lights is pretty small. And the savings projected is also much less.

A compartment has about 120 seats with 8 seats in one section. So about 15 sections. Each section has 3 fans & 3 Lights.

With a guesstimate of 50 W per fan and 30 W per light, that is about 3.6 kW.

Most of the lights are off during day journeys and much of the night. Lights are mostly ON during 4 hours dusk-night time. Fans are ON almost 24/7.

For a 24 hour journey, we are looking at 60 kWH per compartment. Trains usually have about 20 compartments on avg. So about 1200 kWh per ride.

Diesel based power can be reliably put at about 20 Rs. / kWh (Grid power is about 5 Rs. / kWh).

So assuming a completely solar powered ride, about 24,000 Rs. saved for a 24 hour ride. Close to about 370 USD.

About 135000 USD saved per year + additional cost in terms of power gen. eqpt. maintenance, labor, etc.

Most Indian metros already have electrified trains. Only long distance trains are still run using diesel.

Most Indian tracks are electrified back. Only a few diesel trains run right now, on light traffic routes.

The way I see it is, they are trying to save expenses wherever they can so they have budget for other major projects. India imports pretty much all of its oil spending precious foreign currency reserves. So if they can save few thousand litres of fuel every year that's a good saving.

Secondly, IR has ambitious project to electrify all major routes, please see section 5 of the link for ongoing projects (a total of 20k RKM)

http://www.core.indianrailways.gov.in/view_section.jsp?lang=...

Thirdly, there is huge ongoing project to set up dedicated freight corridor across the country. To separate freight and passenger traffic.

http://dfccil.gov.in/dfccil_app/Home

Here is one of the drone videos.

https://www.youtube.com/watch?v=5aHSVVR7Z0A

Lastly, they are spending huge money on modernizing the train stations.

https://www.irsdc.com/

All these have to come from the same annual budget (except dedicated freight corridor project)

The only good thing about this is that it will be an example for what to not waste money on.

This could end up being a huge deal. The one thing I do worry about is thieves making off with the expensive solar panels. The article doesn't mention how the trains would be protected in those cases.

It also doesn't mention if the passenger cars would draw electricity from the locomotive during nighttime/ monsoon etc. but I'm guessing that is the case.

They're likely welded on - if there's a risk of theft there's already a lot on the coaches - lights, fans, tanks etc that need to be protected. Don't think the panels add to risk in any significant way.

Aren't solar panels more expensive than tube lights or fans though?

One more thing to consider is: Stones or other obstacles thrown on the train (which happens sometime due to protest and theft attempt) and can damage those panels. I don't see that being handles in any way.

This comes off largely as a PR exercise given the fact that the train is most likely going to be using solar a fraction of the time and when it does, it won't contribute much.

Electricity is weightless... Leave the power plant at home. Just transmit the electricity by wire (if an electric train) or don't at all if its a coal train because I GUARANTEE the weight of the solar panels alone will make the train less efficient. And if it doesn't, the inefficiency of them being placed in a STATIC (i.e. not sun tracking) position on a MOVING object will certainly destroy whatever "efficiency gains" you had in the first place.

What's next? A nuclear power plant in the trunk of my car to power my radio??

Also, why use solar panels to power interior lights? You only need lights when the sun isn't out. And when do solar panels work? So now we're hauling batteries around the city too.

WHAT. A. WASTE. And what's frustrating is I see bullshit like this everyday!

Consider that building powerlines or a third rail is more complicated and expensive then plain track.

Consider that solar panels on a train are a pointless expenditure that decreases efficiency and increases the train's carbon footprint.

Choose the third option. Do nothing. It's better for the environment and their wallets!

I didn't down vote you. But, I wanted to put some views here:

> if its a coal train

No coal trains in India except Heritage pieces.[1]

[1] - https://en.wikipedia.org/wiki/Indian_Railways#Locomotives

You have a point. But, consider this:

- Currently 47% kms length of the running track is electrified. They are not doing away with electrification and completely going solar. - Currently they have 5869 Diesel and 5214 electric locomotives in total. (almost 47% again.) [2]

[2] - http://www.indianrailways.gov.in/railwayboard/uploads/direct...

The Diesel ones have an Auxiliary power units to save Diesel which they are hauling around anyway now. Your point of hauling around batteries and equipment even now happens in all Diesel locos with multiple compressors and stuff. [3].

[3] - https://medhaindia.com/index.php/products/fuel-saving-soluti...

The Solar changes will mostly augment the Diesel units progressively thus strategically reducing dependence on Diesel, which India is a huge importer every year.

The Strategy is twofold as they are speeding up electrification plus thus reducing the share of Diesel locos and also experimenting with Solar stuff.

> No coal trains in India except Heritage pieces.[1]

Sorry, I meant diesel.

> The Diesel ones have an Auxiliary power units to save Diesel which they are hauling around anyway now. Your point of hauling around batteries and equipment even now happens in all Diesel locos with multiple compressors and stuff.

Consider the energy density of diesel versus a lithium ion battery. Now consider the weight of an array of solar panels versus a small diesel generator. It's a great deal of weight gain. The compressors you carry are a sunk cost and are irrelevant.

The weight gains just put more work on the locomotives diesel engine. You will use more diesel in one location.

> The Solar changes will mostly augment the Diesel units progressively thus strategically reducing dependence on Diesel, which India is a huge importer every year.

You're not reducing diesel consumption. You're just moving it from an array of generators to the engine.

It's nice to see innovation in the railways. Kinda sad in the UK we don't seem to do much, if any, innovation these days :(

What about the people who ride on top of the trains? Is that practice no longer going on?

The only time I ever witnessed that was when a public transportation company employees went on strike for a month and the only transport available were trains. Otherwise I have never heard or seen anyone sitting on top of a train.

Maybe its something from western movies then?

http://www.telegraph.co.uk/news/worldnews/asia/india/7260838...

Actually, that picture makes you believe that so many people sit on top of trains. There are crazy people all over the place. The ones in India do crazy stuff like sitting on top of a train. I have never seen that but there is a possibility that it may happen occasionally but not at the scale shown in that picture. I think India didn't even have a law that restricts people from sitting on top of trains and now they introduced one.

But won't they get blocked when everyone starts dancing on top of the train?

do they have them behind bars same as priso...ehm passengers? very safe in case of accident...

Instead of wasting money on this stuff they would focus on feeding those poor people.

You know they could do both? What's with the feed poor people don't do space exploration, medical research argument? Saving energy, reducing pollution all help lift the quality of life of people.

yeah. that'll ensure there are more poor people. investing in infrastucture means reducing costs for moving from point A to point B, which means more opportunities for people to move up the wealth chain.

Any infra investment should be seen with the POV of reducing poverty in the future, instead of being short sighted and asking "why not feed the poor?".

If you are so concerned about the poor, what are you doing here ? Go feed the poor and then preach!

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