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Another Solar Power Use For Vehicles

06/26/2014 5:12 PM

Fellow CR4 Members-

There have been numerous questions and proposals for the use of solar panels and solar collection systems posted on CR4. He is another one which might be of interest to members. It details the installation on fire trucks, similar to some of the larger mobile units discussed previously. Is it feasible? Do you see any application for the principal of it? How would you use or modify it for your own needs? Any problems foreseen. What is the potential other than fire trucks? Give us a piece of your mind!

http://www.firerescue1.com/fire-products/apparatus-accessories/articles/1934440-How-to-solar-power-a-fire-truck-or-ambulance/

Good Luck, Old Salt

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#1

Re: Another Solar Power Use For Vehicles

06/26/2014 5:54 PM

So many comments I could make.

Is it a good idea, as apposed to just running the engine and alternator to charge the battery, no in my opinion. I can think of better things to carry on a fire truck and ambulance than banks of bulky heavy silicon solar panels and lead acid batteries that will seriously effect vehicle performance and carrying capability.

Want better standby life, increase the fuel tank size, not reduce the vehicle fuel economy by adding gimmics.

Solar panels and batteries ain't going to make the vehicle independent on the engine to power all the electronics let alone the pumps (which I assume are still powered by the engine)!

Reduced carbon footprint my ar$e! These are fire trucks, how much carbon footprint do you think an actual fire generates in comparison to any potential savings a fire truck may theoretically generate.

:(

Independent generation at a site where a long term stay by emergency vehicles may be required is a good idea however, but still rare. There are products for this (mobile generation, dedicated mobile command centres, etc).

Lets not mess with our emergency vehicles.

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#2

Re: Another Solar Power Use For Vehicles

06/26/2014 6:13 PM

Sure, why not? It's good PR for the team, whether it makes good economic sense, well that's where us nit-picky engineers come in.

There's really not much roof area and certainly you don't want to cover up the unit id so the choppers can't id you. Then there's the fact that the panels are going to lay flat which means that unless you're near the equator the angle of incidence ensures that only a fraction of the available yearly energy will be captured. Conventional wisdom is that the panels should be at angle to the horizon that is equal to the latitude, and 0┬░ (horizontal) is a lot less than that.

Without going back to my research library a flat panel will capture less than 25-30% of the incident energy between the spring and fall equinoxes, after that the highest angle of the sun drops so low in the horizon so fast that the maximum capture when coupled with the rapidly shortening days is less than 10-15%, basically you're not getting much bang for your buck...and we're ignoring efficiency.

Then there's the practical concern of keeping the panels clean and sealed against the harsh environment, high heat, smoke, dirt, ash, falling debris, etc. that emergency service vehicles normally operate under.

So, if you want to put a few of those dashboard size portable panels in to trickle charge your batteries then go for it.

There is a much more productive approach that can be considered by anybody who operates a fleet. Put up some carport structures facing dead south and mount panels at the correct angle for your location and use the output to charge batteries and/or utilize inverters to power your communication equipment instead of utilizing utility power. Serves two purposes; cuts the electric bill that the community has to pay, and makes you look "green" for the local tree-huggers, especially if you get grant to pay for the solar equipment.

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#4
In reply to #2

Re: Another Solar Power Use For Vehicles

06/27/2014 12:55 AM

Something about your math is not right. (angle vs. output)

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#6
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Re: Another Solar Power Use For Vehicles

06/27/2014 12:53 PM

A lot depends upon your location, the yearly amount of insolation falls off significantly north of the Tropic of Cancer, since above that latitude the sun is never perpendicular to a flat surface at any time in the year.

http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook/atlas/serve.cgi

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#3

Re: Another Solar Power Use For Vehicles

06/26/2014 6:57 PM

I had two solar panels on my boat, one for each battery.

It was kept outside, in AZ, so they made sense and worked well, I guess. Never had problems starting it before I put them on the boat.

Now, this does not make sense even here, even for emergency vehicles.

Solar panels can only work for about 25% of any vehicle's service life, if that.

Rain, clouds, darkness all diminish the worth of these not-so-cheap to install/maintain systems.

Get a small, quiet Honda generator (not an endorsement) and mount it somewhere on the rig if you want to shut the primary engine down.

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#5

Re: Another Solar Power Use For Vehicles

06/27/2014 12:05 PM

Very good and well thought out comments so far. Please keep them coming. This is a subject that is going to come up more frequently in the months ahead. Thank you all!

Good Luck, Old Salt

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#7

Re: Another Solar Power Use For Vehicles

06/27/2014 11:17 PM

I'm, surprised that no body has mentioned, yet, how ineffective these would be at night.

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#8
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Re: Another Solar Power Use For Vehicles

06/28/2014 2:35 AM

Probably need a combination with Lunar panels? Rain collectors?

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#9

Re: Another Solar Power Use For Vehicles

06/28/2014 11:52 AM

Funny how Lyn mentioned that this will not work at night, etc. and still got a good answer (which I firmly support, unless you live in the "City of Lights"). However, others mentioned the solar panels not working in the dark, and were graded off-topic. By the way, there already is an apparatus engine on board to keep things up and running. I am not a fireman, but I passed for a lumberjack once.

Stop adding things to FIRE trucks that have nothing to do with fire. Let the EMT's handle the EMT work, but this depends on the needs of the community.

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#10
In reply to #9

Re: Another Solar Power Use For Vehicles

06/28/2014 12:20 PM

If you are referring to 7, "I'm, surprised that no body has mentioned, yet", I think it clearly indicates that the author of #7 did not bother to read the previous posts before making his comment.

I marked it OT because I thought it was inappropriate. Like everything else here, it's just an opinion.

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#13
In reply to #10

Re: Another Solar Power Use For Vehicles

06/29/2014 2:58 AM

You know Lyn, I really did read through all the preceding comments and didn't see any mention of nighttime uselessness.... so I read again and sure enough you said "darkness".

Dark things happen in the daytime too.

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#11

Re: Another Solar Power Use For Vehicles

06/28/2014 12:20 PM

Sorry Sir, we can't put your your fire out, we need its light to keep our batteries charged.

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#12

Re: Another Solar Power Use For Vehicles

06/28/2014 12:24 PM

Won't save a thing it is a waste of money. A dead or drained down battery is not the only reason an emergency vehicle will not start. So they will be left running anyway once they are on the scene. Looks good on paper all the savings that they will get. But it's about saving lives. No one will care that you gone green with solar panels. If their love one dies in your ambulance because it wouldn't start for a list of other reasons other then a dead battery.

Sounds like a gimmick to reap funds from emergency services that could be put to better use.

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#14

Re: Another Solar Power Use For Vehicles

06/30/2014 11:13 AM

Ok, OS, here goes,

I am a firm believer in solar power. Not as a primary source though. I understand the limitations and such but do not let them immediately discount the practice.How and where are two important topics of this discussion.So here is my theoretical application of the HOW. First and this is very important. This is not "Solar Powered vehicles" as such. This is, shall we say, solar assisted vehicles.

Fire trucks, back in the day before infrastructure, needed to carry water. In most cities today that is a vestige of days gone by. A modern urban firetruck needs to be a mobile pumping station, men and equipment hauler. This will then free up considerable room and weight for batteries and such.

Solar panels on the equipment is not a good idea, especially on fire trucks due to their use and proximity to hazardous conditions. Most ambulances do not have anywhere near the roof area. Both vehicles are parked in doors in most cases. However, the station itself does have a roof. Granted this only works where the sun shines. This is a limitation and I do not see this as an option for "sunny" old England or any place the sun don't shine.

Both these vehicles have to slow and accelerate frequently when called to duty. (Ever take a ride in one say in Chicago and you will need heart medication pretty quickly) By design, this is something a diesel engine does not do efficiently. You want to run at a continuous speed and load, diesel is your best bet. For accelerating and decelerating heavy objects electric is your best bet.

In Madison we use electric dual power busses. It has cut fuel costs on those busses by half, and maintenance is likewise reduces compared to diesel only units. It takes a lot of diesel to accelerate and produces lots of nasty smoke for those in traffic which this sytem eliminates, also less brake wear is another benefit. All diesel only units are due to be phased out by 2016 BTW.

Next, dual drive is not needed as most runs to service are short and well within the range of electric power. The needed power on site can be provided by diesel generators of much smaller size and better efficiency than a main drive unit running a PTO. Or, forward thinking here, In the case of fire trucks hydrants could also be electrical power stations. (Theft is an issue. I know I live in America and I know this is not currently available, thanks.)

As for ambulances, they are not usually in need of long term hook ups so we can stick with the smaller onboard genny to run the AC and lights and such. In both applications any excess could be use to recharge as well. The fuel savings and reduced brake and mechanical wear and tear would be a plus to offset the initial start up costs.

So there is my concept proposal. Thanks for reading.

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#15
In reply to #14

Re: Another Solar Power Use For Vehicles

07/01/2014 2:29 PM

I say skip the electric hybrid, and go straight to the hydraulic-ICE hybrid. Hydraulic is mainly for accelerating and decelerating the vehicle. There is weight savings to be gained, and better control of vehicle with drive/braking motors on all hubs. Also, the hydraulic could be tapped to provide drive for auxilliary electric power, and water pumping. The ICE has to be large enough to keep hydraulic driven pumps at 100% + emergency factor.

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#16

Re: Another Solar Power Use For Vehicles

07/03/2014 11:37 PM

Thank you all for you taking the time to respond to this thread. Almost all of them were well thought out and highly informative. Several of the points you brought up I am going to use when one of the "sun shine huggers" starts telling us how to construct a fire engine, whichever type it may be. Fire engines are a multi-purpose vehicle. At the least an engine (pumper) is a transportation vehicle, both manpower and equipment. Although it may not seen like it takes much brains to specify and design one there is a lot of time and skill involved with buying a new one. Even the cheapest with minimal capabilities costs at least $250,000, with the average going for $400,000 to $600,000. A ladder truck usually costs in the neighborhood of $750,000 to $1,200,000. This all dependent upon what it comes with.

My viewpoint is that trying to mount solar panels on a vehicle that uses every inch for all the equipment carried and needs to be deployed is either a waste of money or mounting a panel in a place that has better uses,

The electrical system on one is usually a 12v - 200amp or up to 300 or more amps. All those flashing lights need power. Add to them the radios the special equipment such as tower lights, water utilization devices, etc. and it uses up all that power and sometimes begins to shut down nonessential uses. The panels used in California have an output of 6-7 amps at 12v. Not very efficient for power/surface area factor when you have 2-300 amps off the diesel engine. When an engine is standing-by at an incident the output of the panels isn't of any value. Also in that situation the engines are not usually shut down so that the vehicle is ready in less time for fire use.

If your neighbors or your own, house was in trouble would you want any time with solar panels delaying the response?

What many depts. use when parked at the engine bay are power cords with connector ejectors connected to a battery charger usually with a capacity of 30-40amps. The ejector is activated by the starter switch and the connector goes away. Same with compressed air to the brakes.

Hydraulic generators are usually used to power 120/240v equipment. The bright raise able light towers are often run with this but not always. Advance in LED now make 12v more popular.

Where would you put the panels? The cab has lights on it; behind it are the monitor (high volume nozzle permanently mounted); the pump panel; the hose bed; and finally the rear compartments. Anywhere it is put them they are going to be in the way.

Solar panels, NO! More beneficial equipment, YES!

If you would like to see why, go to your local firehouse and ask for a tour. They will be delighted to accommodate a tax payer.

Thank you all.

Good Luck, Old Salt

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