Modifying purchased street lights.

Welcome everyone, I'm new here and new to solar, but I don't intend to be new for long. Always been interested in alternative energy (solar/wind), but just now getting around to doing something about it. I have a business that I would like to install a solar water heater as well as some PV panels, but I want to learn a bit before I tackle that project. Now, to get me started.....I purchased some used street lights. (not antiques...don't I wish) I would like to put them around the parking lot and power then with solar. I'm thinking...a PV panel, batteries, and inverter (on each light)...and I'm good to go. Am I missing something? Please give me any tips/tricks/look out for's/been there's/etc. Like I said this seems like a simple project, and then it's on to bigger and better.

PS: equipment brands and where to buy would be helpful. Thanks.

PSS: Our governor (Iowa) keeps talking about alternative energy, but nobody wants to provide any incentives. My electric provider is a co-op, they have provided me info about their 'buy back' program. Bottom line, they don't want to buy excess energy. They make it more trouble (and expensive)than it's worth. That's their plan....sorry..just venting.

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Modifying purchased street lights.

    First, you need to decide "How Much Light" is wanted from the lights. The 3 watt LED bulbs are quite bright, and a 9 watt cluster may be enough. If you are expecting the brightness of an average 50W Hi pressure sodium bulb, best to use the Hi pressure sodium, at 5x the power draw.
    Do the lights need to be on at all hours, or maybe just some hours - Morningstar has a timer/controller/charge controller that may work for you.

    When you know the size of the battery you need, get a box to mount it above vandal reach, and enough panels to charge the battery size.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Modifying purchased street lights.

    Usually, the most cost effective (and energy efficient) solar electric installation are Grid Tied Inverters (no battery--Solar PV connected to Inverter connected to your Utility Power) and net metering (1 year best, many have 1 month terms). Basically your utility acts like a giant battery for, hopefully, only a minimum service charge, plus any electricity that you consume over and above what you generate.

    Depending on how much power you consume and what your rate structure is--you can really save money (i.e., if you power costs $0.25 per kWhr or more, you will probably truly save money in the long term--if your power is less than $0.15 per kWhr, then you are just getting ready for the future when electricity rates eventually rise).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Modifying purchased street lights.

    First, the lights will be around a parking lot in the country on our farm. No vandals etc. The business is a wedding chapel my wife has here in the country. I'm thinking of building a brick 2x2x3 base to mount the poles, and put a door on the back side of each base so that I can hide the batteries inside the base. They will only be used for evening weddings, which is usually on weekends and then only for 2-4 hours per wedding. Is it possible to wire one (similar to a mercury vapor light) so that it will come on when it gets dark, and off again at daylight. The rest will be a switch per light (because I'm to lazy and cheap to wire them all on one switch. Is that possible, maybe only need one inverter then. Like I said, I'm new to this but I'm peddling as fast as I can.

    As to net metering....NOPE...private co-op. They aren't required to buy back like the public owned utilities.

    Thanks.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Modifying purchased street lights.

    If you have days to recharge, great, but if you use Fri, Sat, & Sunday, the batteries will die quickly from being undercharged.

    I'd really use one inverter per fixture, you can get some 75 - 100 watt inverters at computer stores for laptops. They output a square wave,
    and the " *.vapor " lamp ballast may not like that. There are 12V CLF bulbs that may work for you though.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: Modifying purchased street lights.

    Pigpen,

    You may be able to retrofit the lamps with LED assemblies like these: http://www.superbrightleds.com/MR16_specs.htm

    If you use DC lamps, you won’t need an inverter, but you’ll have to be careful about wire size and length.

    Here’s an interesting new inverter with hardwire remote control: http://www.morningstarcorp.com/products/SureSine/index.shtml

    A charge controller like this one can be user programmed to turn on lights or other loads:
    http://www.morningstarcorp.com/products/SunLight/index.shtml

    You’ll also need PV modules and batteries. Sizes will depend on estimated energy requirements (kWh/day), solar insolation, and perhaps battery temperature.

    HTH,
    Jim / crewzer
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Modifying purchased street lights.

    I was looking through some of the information on Iowa's Harlan co-op's power rates... And see that they have an interruptible rate that is as low as ~$0.03 per kWhr (intended for electric heat at night?).

    At that rate, I wonder if you can forget the solar and just install a battery bank and use an inverter/charger instead. Would seem to be a great way to save money.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Modifying purchased street lights.

    Just a question regarding your expectations. What wattage are these used street lights, and if for example they are 150 watts each, are you planning on needing or using that much light? Since as you say, you are new to this kind of thing, I believe we have to know this first, otherwise we could be talking about two different realities.
    Mike90045 already asked basically this same question, but I see no answer.
    Thanks
    Wayne
  • System2
    System2 Posts: 6,290 admin
    Re: Modifying purchased street lights.

    Sorry, I don't know the wattage. The street lights are still in place and won't be removed from their current site until the first part of August (when the new ones are installed). I was just trying to get a head start on the project.
    As to the amount of light required/expected. I'm just wanting enough light in the parking lot so that the guests don't have to stumble in the dark to their vehicles.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Modifying purchased street lights.

    Reason to ask is that a solar/battery system would cost, very roughly, anywhere from about $15-$30 per watt (peak) generated.

    Say, for example you have 5 hours of sun (a pretty sunny location--probably does not apply to winter/storm seasons) and you want 10 hours of "light" every day and XX watt lamp...

    System capacity = XX Watts * 10 Hours * (1/5 hours/day Sun)/(75%panel-eff*80% batt-eff*85%inverter-eff)

    System capacity= XX watts * 2 * 1/0.51 = XX Watts * 4

    So, if you have a 150 watt HP Sodium lamp, you need a 600 watt system (plus panels, batteries, controller, structure, etc.)--which would be about $900-$1,800 in parts and installation...

    If you wanted a 35 watt HP Sodium lamp, that would be a 160 watt system or $525 to $1,050 system...

    Of course, you can get LED Lamps, save the cost (and losses) of an inverter.

    If you only need light twice a week, you can size the panels smaller and the batteries bigger. If you want this system to work in the winter too--you would probably need either to make the system 2-4x larger, and/or add alternate power sources (grid charging, generator, wind, etc.) as a backup.

    For US Solar data, look here... Find your state and nearest city. I suggest the PDF file--much easier to read and look at the plotted data (range of sun over thirty years).

    The above numbers are just a point for discussion--depending on your actual needs and which equipment you purchase (new/used/etc.)--prices can be above or below those that I have posted here.

    -Bill

    PS; you may wish to look at a lighting catalog--usually they have charts and recommendations for lighting--sometime local building codes/planning commissions also have their own requirements... Lastly, pay attention to what sort of lighting there is around your area and what kind of feeling it creates. You probably don't want a base-ball field level of daylight type lighting--but you may not want the orange-ish lighting of low pressure sodium (among the most efficient lighting in terms of Lumen/watt).

    Lighting that is expected in your area by customers vs that expected in the downtown of a large city probably differs too.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset