# Solar panels on car roofs?



## Mailliw (Oct 15, 2022)

So I had an idea while randomly watching YouTube videos on RVs and vans. Would putting solar panels on the roof of cars make any sense? Could solar panels & batteries augment or replace HEP? Or would maintenance issues outway and benefits?


----------



## GDRRiley (Oct 15, 2022)

I'll use 20W per sqft which is really good for solar right now
a venture car is 85ft long and 10ft wide at each end there is ~10ft with vents. so lets say we can cover 65ftx10f= 650sqft= 13,000W
good enough when the suns perfect to cover about 1/4 the HEP needs of a coach car 

So its not going to replace HEP any time soon


----------



## Just-Thinking-51 (Oct 15, 2022)

Not sure the return on investment would be there. Solar panels would technically save some horsepower from been used to generate HEP (Head End Power) To be effective you would need a storage system (batteries), and that weight and space.

When a locomotive start to move it has more than enough power, so a battery booster system is not need. (In freight service we have slugs. The mother locomotives will provide power to the calf [traction motors and concrete weight]. So when starting the excessive power will go to slug. Then as the train pick up speed the slug will stop getting power to its traction motors, as the mother locomotive needs that power to go faster.

So the advantage that I see, would be longer trains. Less voltage need to travel thur the HEP cords, as each coach would have the ability to cover any spikes in demand, and decrease the power requirements thur from the locomotive. You can also get soft start for the HVAC system to even out any start up demand, even with out the batteries and solar panels.

In recap if you did this it more of “green wash” than actually savings.


----------



## Qapla (Oct 15, 2022)

If Amtrak can't keep the windows we look out of clean - would they really keep solar panels on the roof clean enough to be effective?

Reducing the size of cables from the HEP would not be a good idea because, unless the solar was operating at efficiency all the time, that excess power would still need to be supplied by HEP - like, at night.

It is also not just the cost of the panels. For this to work, each car would need large power inverters and a battery bank with enough reserve to power the car when solar is not available and HEP is not being used. 

The solar panels, batteries and inverters would be on the order of $75,000 or more per car and require maintenance people trained in solar power.


----------



## Mailliw (Oct 17, 2022)

Thanks. I kinda figured it even if it were a good idea Amtrak is the wrong company to execute it.


----------



## Siegmund (Oct 23, 2022)

A much simpler project, putting solar panels on the roofs of Amshacks in sunny areas, might well pay for itself.

I am hoping to someday see a lot of elevated solar panels above parking lots, so that I can park in the shade and walk into a building in the shade, at the same time as the sun is producing electricity 10 feet above my head. But even _that_ hasn't taken off the way rooftop solar has yet.


----------



## Just-Thinking-51 (Oct 23, 2022)

Siegmund said:


> A much simpler project, putting solar panels on the roofs of Amshacks in sunny areas, might well pay for itself.
> 
> I am hoping to someday see a lot of elevated solar panels above parking lots, so that I can park in the shade and walk into a building in the shade, at the same time as the sun is producing electricity 10 feet above my head. But even _that_ hasn't taken off the way rooftop solar has yet.


How about 15 feet above the parking lot, so a lost truck driver does not destroy them.

From my experience getting solar on my roof, it has been quite trying. Pretty sure the next time will be much easier, but there was so many venders that I had to walk away from. Getting a national system would be a nightmare to deal with. The biggest problem I found was cost. Made a mistake and finance through a vender. Opps cost of project skyrocketed, they did not care, you have financing. Had to runaway from a national company vendor because of that.


----------



## Metra Electric Rider (Oct 23, 2022)

Just-Thinking-51 said:


> How about 15 feet above the parking lot, so a lost truck driver does not destroy them.
> 
> From my experience getting solar on my roof, it has been quite trying. Pretty sure the next time will be much easier, but there was so many venders that I had to walk away from. Getting a national system would be a nightmare to deal with. The biggest problem I found was cost. Made a mistake and finance through a vender. Opps cost of project skyrocketed, they did not care, you have financing. Had to runaway from a national company vendor because of that.


I was in Portugal a couple years ago and the high end grocery stores (Continente) had umbrella's above the car park. Seems like Solar panels above parking lots (and on store roofs) would provide a lot of power and provide shade for cars to boot, keeping them cooler in hot climates.


----------



## MARC Rider (Oct 24, 2022)

Siegmund said:


> A much simpler project, putting solar panels on the roofs of Amshacks in sunny areas, might well pay for itself.
> 
> I am hoping to someday see a lot of elevated solar panels above parking lots, so that I can park in the shade and walk into a building in the shade, at the same time as the sun is producing electricity 10 feet above my head. But even _that_ hasn't taken off the way rooftop solar has yet.


They have that at our local Ikea.


----------



## PVD (Oct 24, 2022)

Funny, I'm just taking a break from re writing night one of a class I teach on alternative energy, which is focused on solar and offshore wind. On Long Island, a number of the LIRR commuter lots have received parking lot canopies, and a number of shopping malls have added them to the roof level of their parking structures. The new Terminal B parking garage at Laguardia sport about 3600 panels on its roof, but they are not canopied since it used not used for parking. Lots of solar (coupled with battery energy storage) used on signals and communication in the area as well


----------

