The existing thread on solar gave me this idea: Solar panels on freight cars to supplement electrical power to the engine. I don’t know if the power output on modern solar cells would be enough to help. I know solar panels are not cheap either. A freight train covered with solar cells would give a lot of square footage for panels. Another down side is I think it would be easy for the panels to get damaged in a RR working environment.
Assuming that enough power could be generated, you’d be better off with one or two “panel tenders” in the locomotive consist than panels on the cars, because you wouldn’t be able to use the same large array on different car types, and you’d have the problem of yet another connection between cars being required.
(UV lamps in tunnels, anyone?)
also theft and damage from vandels is a big issue that will have to be delt with…not to mention the overall costs to put that type of equipment on every car… even if every car wasnt done…the carriers would still have to invest in at least the wireing harness to send the power that is being generated to the head end from cars that where equiped…also what are you going to do with millions of dollors of photo votaic cells that are sitting idel on a side track or in an industry for days or weeks at a time hooked up to nothing…spend millions on equipment that isnt being untilized is always something that the bean counters dont like to let happen…
csx engineer
This was already discussed briefly a couple of months ago - probably under the “Return of Coal” or “Return of Steam” threads (or similar), but here’s an approximate analysis:
The power of the Sun shining on the Earth’s surface is known as “insolation”. It is approximately 1000 watts per Square Meter for a surface perpendicular to the Sun’s rays at sea level on a clear day (from Wikipedia on “Insolation”). At 746 watts per horsepower, that’s a maximum of about 1.3 HP that could be gained from solar panels that are 100 % efficient - and of course, none today are anywhere near that - quoted figures range from 12 to 20 %, if I recall correctly.
To make the math simple, let’s consider a railroad car (say, a box or autorack) with a flat roof surface that’s 10.5 ft. wide x 50.0 ft. long = 525 Sq. Ft. Since a Meter is 39.37 in. = 3.28 Ft., a Square Meter = 10.76 Sq. Ft. Hence, 525 Sq. Ft. = 48.8 Square Meters.
So on a sunny day with the Sun directly overhead, at 100 % efficiency that roof could generate 48.8 x 1.3 = about 63.4 HP.
If we presume that this hypothetical car weighs about 263,000 lbs. (a common maximum gross rail weight “break” for that 50 ft. length), that would be 131.5 tons.
So the HP per ton ratio for this solar-powered railcar would be 63.4 HP / 131.5 gross tons = 0.48 HP per ton.
Any of our members with practical train operation experience can tell you right now that its performance is going to be very anemic. But let’s go ahead and “run the numbers” just to see:
Since 1 HP = 550 ft.-lbs. of “work” per second of time, that would be about 265 ft.-lbs. per sec. of power available for each gross ton of car weight.
If we assume a 1 % grade (for simplicity and easy math), then each ton (2,000 lbs.) of that 263,000 lb. car will need x 1 % = 20 lbs. of tractive e
Assuming that the power was being collected and sent to the head (or tail) end of the train, though, that ~63 HP per car would be 6300 HP for a 100 car train. In a perfect world, that’s an extra locomotive!
At 20% efficiency, however, we’re down to the equivalent of little more than a 1200 HP switcher.
Given the logistics of simply connecting everything (now you have to make the power connection as well as the air), and even disregarding the capital cost, it just wouldn’t be worth it.
My original idea was for the solar power to “supplement” electricity to the traction motors thus saving diesel fuel. I originally felt that this idea was not feasable and several of the replies have confirmed that. But I thought it was an idea worth considering.
We do use solar panels to operate our ballast cars. They are a lifesaver for us because breaking those doors open by hand is NO fun. While your origian idea may not be feasable you were certainly thinking in the right direction.
…For now, it sure seems solar panels are not feasible for suplimenting energy to power train operations…
But I’m sure they do fit to work in some circumstances. How about build a small array of them into automobiles to trickle charge the car battery. Maybe a permanent circuit to run a fan ventilation system for autos that must set out in very hot climates day by day to reduce the damaging heat build up inside. Typically down south or southwest climate conditions especially.
Already being done. You can buy these things at a number of places (Northern Took & Equipment, etc. etc. etc.) and they work just fine, exactly as you suggest, and not just down south or southwest (just don’t expect to trickle charge your car’s battery while it’s in your garage!).
They also work dandy for signals, to charge the batteries, and in a lot of other applications around the railroad where you can charge a battery with them, then use the battery to do something electrically useful. You’d be amazed how advanced the rail industry is with these things!
…I suppose one could leave the overhead light on in the garage to supply a bit of electrons to the solar panels as vehicle is parked inside…Pull itself up with it’s own boot straps…Ha…{just kidding}.
The solar panels would increase the weight of the vehicle. This would have an adverse effect on fuel effency. Of course running the air conditioner affects fuel effency too. ???
Here in Western Australia, we have solar panels powering some of our signals at passing sidings, and providing power for the switch motors as well. I used to drive past one set to the west or Geraldton heading out towards an iron ore mine site, along the old grain network…
Bulbos: in the US solar panels are used for signals as well in locations where commercial power is not readily available and/or lineside power is subject to being interrupted, but in certain locations like the pacific NW there can be too many days of no sun for the panels to work.