Solar Energy Provides An Outlet For Hurricane-Related Woes

Hurricane season in the US Atlantic region officially began on June 1st. While [mikesoniat] is hoping for a mild one in his Gulf Coast town, he’d like to be as prepared as possible in the event of a power outage. He’s been experimenting with solar power lately, and while he’d love to go all out with some hefty system that could keep all his appliances running, solar outlethe’s not quite ready for that kind of investment. While thinking about this dream system, he noticed all the phone jacks around his house that he hasn’t used for several years. After consulting the phone company and researching the capabilities of 22-26AWG POTS copper lines, he devised a solar-powered system to provide enough power to run lights, fans, and a couple of phone chargers.

At the heart of this hack are two 12V solar panels, two 12V batteries in a weatherproof junction box, and a 100W solar charge controller.  He started by re-wiring Ma Bell’s junction box up to the panels with thermostat wire. After prying out the RJ11 jack panels all over his house, he wired in regular outlets and marked them as 12V solar to avoid confusing his house guests. He was able to find 12V LED bulbs with standard bases, so all he has to do is screw in these bulbs and plug the lamps into his solar outlets. He also installed a floodlight outside and ran all of the wiring through the floodlight box.

To soak up more sun for this or any other solar hack, try a 2-axis solar tracker.

96 thoughts on “Solar Energy Provides An Outlet For Hurricane-Related Woes

  1. if he was replacing the face plates he should have used a different connector imho (hate to be *that* guy) what happens if someone else plugs a 12v appliance into a normal socket?

      1. I’m not sure I would do that, I would probably put some 12v plugs (like in your car) in a wall plate, I might even put a USB plug in the wall but you would need to change the volt down

        1. Those “12V plugs like in your car” are the absolute worse choice (oh, wait, second-worst choice after reading this article). They are utter crap and *always* make a poor, intermittent connection.

          PowerPoles, on the other hand, are awesome. They are polarised and genderless, and have a high-current carrying capability in a compact size.

          I should be writing ad copy.

          1. On the other hand, CIgarette lighter plugs and sockets are cheap and there’s a plethora of electrical equipment and appliances already using them.
            Whereas with powerpoles you’d have to either rewire all equipment or make adapters.

            Ih you have to criticize Cigarette lighter plugs and sockets, then criticize the safety of them.
            That (and their size) is the only two valid complaints regarding them.

          2. I love how the only two power standards humanity has managed to stick with on a global scale are USB, and car cigarette lighter 12V. Neither of which was intended to power stuff.

          3. Torque, to be fair, he just finished rewiring his house’s phone line and went out of his way to find 12V bulbs that fit an edison socket. Rewiring some power cords to avoid blowing up appliances in a rare moment of inattention seems like relatively low additional effort.

          4. Split the difference – go for powerpoles, banana jacks (or porcelain-insulated screw terminals from the 1920s if that’s what you like), but make a few “pigtails” – connectors to go between your choice and a 12V car receptacle simply because there are so many adapters/connectors that are already in use for them and Murphy’s Law says you’ll need one sooner rather than later.

            The lighter receptacle WAS designed to power a huge resistive load (the lighter) and they are cheap, sturdy and will carry 10A easily – even if they’re a pain.

        2. Agree, I am not sure it is wise to use a socket that someone is used to using for 120V AC on items intended for only 12V. I smell smoke. If worse comes to worse and you want it to look like an outlet – buy an outlet rated for another country. I would of even used and RH45 and use the VDC pins. The benefit, you could even use the same outlet for ethernet with no issues.

          1. Yup, only takes one time to plug the 12V lamp into the 120V socket. Especially if it’s the same lamp! I’m surprised they make 12V bulbs that fit 120V sockets, that’s the exact same problem as here. Far too much change of burning the house down, protected only by a sticker that many people won’t understand, eg a house guest.

            As pretty much everyone else said, you need a different socket, ANY would be better! Using a foreign mains socket might be a good idea, they’re rated for lots of amps. British ones contain a replacable fuse in the plug too. They’re also nice and sturdy. The only minor downside is stepping on the damn things with the pins up, truly you have not known pain like it…

            Talking of amps, for equivalent power, 12V is 10x the amps, so I’d use some decent cable for it. Thinner cable causes heating, but also voltage drop. When you only have 12 volts, you don’t want to lose half of them in the wiring system. This will be a serious problem if you draw any real amount of power.

            Apart from that though the idea itself is a clever one. If your solar panel generates enough power for constant use, you might even find it saves on electric bills. There’s also inverters that produce mains from 12V, they’re pretty cheap nowadays.

      2. Hmm I was going to suggest Jones plugs, polarized and good for 5 or 6 amps. But good to see these for my information. I standardized on Jones plugs awhile ago for low voltage DC. They are available in 2, 3, 4… etc pins. All polarized.

      3. You beat me to it. Powerpoles are ideal for this, and the powerwerx wall plate is well-designed for exactly this application, fitting a standard inexpensive junction box. I’ve used exactly this approach in my camping trailer, which has a 12V battery, plus has the ability to plug into 120V “shore power” supplied by the utility company at a campground. Both 120VAC and 12VDC are available at various points in my trailer, and nobody can accidentally plug either type of appliance into the wrong power source.

    1. Agree 100%, this is a recipe for fire/injury and completely needless.

      Also, phone wires are NOT power wires, they carry ~50-120v at very low current. Sure, good standard solid copper phone wire (as used by the telcos) is up to a bit of current, but most of the connections are not designed for it (I predict the 1st melted thing will be a junction) and the losses in the cable must be huge.

    2. The power losses are going to be horrible and as others pointed out a fire hazzard using the wrong sockets.

      Much better to use an inverter and distribute 120/230V to use by standard appliances thru these standard sockets.

    3. I agree with what you are all saying about the outlets. The main reason I used the standard ones was so we could use our existing table lamps without rewiring anything. In the event of a hurricane, which can knock power out for several days, I can simply change out the bulbs and plug the lamps into the solar outlets. When power is restored, I can switch them back. I’m definitely willing to rethink that choice. It would be an easy modification.

      1. I like your idea of interoperability of existing fixtures (I live in the Gulf Hurricane region). One thing I would recommend would be the use of different colored outlets like the orange ones for special electrical lines (properly labelled, of course) wired to the solar system. This would reduce the likelihood of anyone attempting to plug a 120V appliance into a 12V outlet. The wild difference in color would attract the eye of the user who would then see the label. An item such as the one here:

        Changing your existing white outlets to a different colored one would be an easy refit of your current system, and the only added cost would be the new outlets and wall plates.

          1. interoperability with current fixtures is a valid reason to use the same hookup type. in addition to different colored outlets, i would also use a baby safety style latch to force people to have to really think about why they are using the outlet.. and it is cheap protection. these things a PITA to remove:

            alternatively, you could wire the outlets with a dc specific outlet, and then make some custom pigtails to convert to your standard nema plug for your lamps when needed

        1. I think another reasonable option would be to use child-safety inserts to block off the plugs when they’re not in use. That’ll greatly reduce the risk of someone blindly plugging into the socket.

      2. Here is a thought: Make some lights for daily use that run on 12V with a special DC plug. Get some standard 12V supplies that you either wire to the same outlets as the solar powered 12V (with a switch or relay to change the source) or have standard and emergency 12V outlets.

        A suggestion for the lights are cheap 12V MR16 LED spot lights.

        If you go for the automatic relay option the lights won’t even go out when the power goes :P

    1. HUGE FAIL!

      seriously, if I was a h.a.d. editor I would not publish this due to the very wrong plug being used!!

      re-using sockets and plugs is a common diy thing but *NOT* for power!

      not, not, not!

      I cannot say this enough!!

      bad bad bad bad bad!!!

      readers: I’m sure most of you know better, but please don’t ever do this crap!

  2. Even the power sockets themselve look shocked by their misuse :P
    Cool idea, but it’s not that hard to install proper wiring and sockets if the pipes are already there.. please keep it safe and don’t burn your house down.

  3. Lot of haters on the use of standard sockets, but not a lot of constructive ideas or criticism. Saying its a fire hazard in and of itself is ridiculous, all you can see is an outlet and he may well have wired in overcurrent protection of his own (and, come to think of it, solar panels provide inherent overcurrent protection). Also, The guy wired it up himself and labeled the outlet to his satisfaction.

    I would question the following on this installation: Is the installation legal and compliant with code in your municipality? How will that effect you in the event of you needing to file an insurance claim or sell your house?

    1. After RDA. The only possible practical hazard is due to using the high gauge POTS line with the batterys. A short across the wires would result in a high current due to the batteries (not because of the solar panels as the power output of those is naturally current limited). So in addition to verifying code compliance, since its a low watt system, I’d say it might be a good idea to just wire in a dinky little fuse in there somewhere.

      1. Just one more thing. The guy says the install is in the Gulf coast, but since I’ve lived in the midwest most my life it gives me pause to see a battery installed outdoors. If this were installed somewhere actually gets winter, I’d add a little thermostat and a heater in the battery box, or just install them inside the house.

    2. There’s another side to this, though. If the home has these 120VAC-style outlets carrying 12V, surely there is something around the house that is intended to be plugged in to them. He’s talked about using them for table lamps with a 12V edison style bulb. Assuming the bulb is incandescent, if you plug that into a 120V outlet, the bulb will be destroyed quickly, probably with no harmful side effects. But what happens if other 12V devices get wired up to use these outlets, and then get plugged in to 120VAC?

      For example, it would be logical to make a pigtail adapter with a 120V plug on one end, and a cigarette lighter socket on the other, to allow a 12V phone charger or similar 12V device to take advantage of these outlets. That would be fine until someone accidentally plugs that pigtail into a 120V outlet.

      Sure, it’s all fine if electrically-literate hackers are the only ones in the house. But consider kids, or clueless visiting great aunt Madge, etc.

  4. We use mains sockets for our 12V spot lights that are used in the hunting season. They are way more reliable and secure than those stupid cigarette sockets and we had mains plugs around so that is what we went with.

    To keep things safer we wired the plugs such that the positive and negative are across the earth and live prong. That way, should someone try and plug the spot light into an actual mains plug, only the earth leakage would trip. If a 220v appliance is plugged into the 12v socket, then nothing would happen.

    You should maybe consider doing this if you are going to stick with using the mains plug. Guests do not read labels on plugs.


    1. Earth and LIVE?? Why not earth and Neutral? Then if someone plugs something in like a bulb that has blown (so there is no leakage), you don’t have a 12v appliance with 220vAC floating around inside.
      Also, the time for an ELCB to blow is likely long enough that you can blow the bulb, so someone is then going to try and plug it in somewhere else to see if it’s the appliance that’s fried or the socket and have the problem above.
      Neutral – earth will still trip the ELCB but should have a lot less likelihood of killing someone.

      1. What I did with a similar setup in Italy was short the live and neutral prongs together (so that it’d trip a breaker if plugged into AC) for the positive, and earth for the negative. The advantage is that it’ll trip a breaker immediately if put into AC, and the transient high voltage stays in the plug and doesn’t touch the 12V appliance.

      2. I was just reading up on mains wiring now. It is possible we wired across earth and neutral.

        Just a side note (I might be way wrong), but in South Africa live and neutral is not polarized. In the case of double insulated portable appliances where only a 2-wire conductor is used, the plug cannot enforce polarity. Our South African 2-prong plugs can go in any way around.

        Also, we are talking about a plastic 12v spot light. There is no way you can contact any of the electrical parts without smashing the thing open, so that’s okay. Earth Leakage trips in SA is veeery fast. I have played with mains a lot when I was a small boy, and I have never seen any big sparks from shorting to earth. It’s really high impedance and it trips as soon as you make contact.

        And I have NEVER EVER EVER seen neutral and earth connected to each other within an appliance (apparently this is standard practice in the US?). And it will most definitely cause the earth leakage to trip immediately in SA.

    2. Do you use 6-inch nails instead of fuses too? They are also very reliable. Even if your house bursts into flames your fuse box won’t let you down.

      Seriously, use a DC connector, not a mains connector. PowerPoles are usually the best choice.

      1. Power Poles are NOT the best choice. They are not available in South Africa, they are way more expensive to import than anything we had on hand, and they are especially out of the question when the closest thing resembling a city is a ~250km drive away. We only had mains plugs and sockets at hand, so that is what we used. 5 years later everyone is still alive and kicking.

        The best part, we don’t have dumbass running in the family.

    3. Thats not a bad idea. Also would up the current carrying capacity of the wires. YOu coudl tie all phone wires to +12v and The grounds all to earth.(like they do in cars).

      1. Also another side note you can get dc to dc, up and down converters fairly cheap on ebay,1-2$ IF you ran your wires at a higher voltage say 24 you can get more amprage out of them then down convert at the outlet box.

    4. I’m glad I scrolled down before posting this very suggestion and yes between hot and neutral (read white and black) if you have GFCI on all breakers… otherwise you will blow the device (I’m guessing UK etc. since you have 220v as your appliance voltage) for the rest of us .. perhaps use 12v between neutral and ground (read white and green/bare) and place an idiot light across hot and neutral and as long as you don’t have separate earth/neutral (read a electrically bonded neutral/earth in your circuit breaker box) and or a fault (read incorrectly wired wall receptacle, a shorting device plugged into the other half of the receptacle, etc) no harm no foul although, maybe place a fuse in the lamp for the hell of it..

  5. phone boxes are phone co property so the phone co may not like you using their boxes.

    i know the cable co gets upset when dish uses their boxes to run the cables

  6. OK, I’m going to be the contrarian here: This was the *best* choice for connectors. They are cheap and readily available, unlike the alternatives offered in the suggestions. They will stay in and make a secure connection, unlike the cigarette lighter connectors suggested.

    Admittedly, the gauge of wire used might be a bit on the small side, so upgrading the system later for higher current would require some replacement of wiring. But for now you aren’t going to be using appliances with this system. It is for emergency use.

    Well done mikesoniat! Thanks for sharing!

      1. Hmmm, $14.99 a piece for Powerpoles wall plates, plus the the ends you have to put on all the lamps (which are now no longer able to plug into standard outlets), ordered online, plus shipping. Or $3.69 for a pack of 10 duplex outlets available at any hardware store/home center. Plus it’s a hack, you know, using stuff the way it’s not intended originally.

    1. Thank you for your comment, Nater. Thank you for understanding this is for emergency use (and the occasional fun of saving energy). I don’t have random people walking around my house plugging things in. It’s a pretty controlled environment.

    2. Loads of connectors are cheap and readily available, and ANYTHING is preferable to using one that most people will expect is a mains socket (or in this case, using the same plug on your 12v device that will fit into a regular mains socket).

  7. Ouch!, what everybody else said, using mains connectors is not a good idea. I would use the standard barrel connectors you get on most low voltage devices like. Would be easy to use a blank wall plate and drill a hole to mount something like this

    Then using a barrel-plug to barrel-plug cable you connect many 12v devices easily.

    I’m not sure I would re-use the existing lamps but perhaps use some 12v LED lamps with clips that could clip on to the lamp base.

    1. swap out the 120 outlets for female barrel connectors – make cables that with male barrel-plug and wire it to stand alone outlet boxes that have your 120 socket. During emergency – unplug lamps from 120 – swap led bulbs – break out the “custom extension dc to 120 outlet cords” and plug your led lamps in

      1. UPDATE: Due to lots of helpful suggestions (and a few outright warnings) regarding my choice of a 110 volt plug for the power outlet, I decided to add some optional 12 volt outlets to the project. Please see Steps 1 & 3 for details.

  8. Further more .Pictures do not show fuse holder or text does not mention installation of fuse.
    THIS is important because amatuers easily over look safety itiems because circuit will
    still function with out them..

  9. Any easy and safer fix would be to use the 220V outlets that have the pins horizontal for your 12V circuits, and wire the lamps with a twist-lock plug and make adapters of a twist-lock socket and either a normal or 220V plug. – this should give you the ease of changing to 12V bulbs, and the time to make sure you are plugging into the right power socket.

  10. Mike:
    Sorry to see everyone is jumping down your throat for your simple solution to your problem. HaD has numerous projects with a high likelihood of FIREY DEATH and yet suddenly using the wrong plug has everyone in arms.

    Don’t get me wrong, I understand the risks, and I suspect you do too. That doesn’t mean 20 some people need to repeat the same thing….

    So anyway, moving on to solutions (if you feel you need to take action) that don’t involved putting in different receptacles and wiring dedicated lamps…. I would suggest using the child safety plugs that can be inserted into the receptacles to block them off. This would be a pretty simple solution to keep people from using the wrong plug, if that is a concern in your household.

  11. I can understand the cost and availability of the plug. I agree with most…. Its a bad idea, but it is your house.
    That being said… I would suggest painting the cover plate red, label both upper and lower outlets as 12V and put child safety plugs in. Also make sure everyone in the house knows the correct procedure for use.
    I like a good disaster preparedness system. Extended power outages are NOT fun.

    1. The problem is not with the 12V outlets, plugging a 110V device into a 12V outlet is not likely to do much harm. The problem is that if a lamp has been fitted with a 12V bulb and someone forgets to switch it back to a 110V then (especially if it is LED) that could go up in smoke in quite a spectacular way.

  12. Neat but of marginal value after a hurricane. Light is handy but you will really want to power your refrigerator and some fans. If you are on a well and not city water you will also need to power your well. AS time goes on you will really want to power a tv or your router and or DSL modem.
    After a hurricane without flooding this the order you will get things back usually.
    1. Phone and or DSL.
    2. Power.
    3. Cable and cable modem when they dang will want to give it back to you.
    BTW Been through 5 hurricanes and a few tropical storms.

  13. nice hack
    I’m not so concerned about the plugs,
    I’m a bit wary of the airtight sealed box for the batteries.
    I understand that storms are wet and that sealed lead acid batteries with a charge controller should be stable, but I’d be more concerned about strapping a bomb to the side of your house. Is there some ventilation?

    But good use of the existing wire! I didn’t think you could get up to 3 amps on 26g wire? especially at the distances run in the house. But, you are doubling up the lines I see.

    1. Gel batteries do not gas… Having said that, his batteries look undersized for anything but the shortest outage given that you can’t discharge them > 50% without causing long term damage. I have a similar solar based emergency comms and lighting setup (I use car lighter sockets myself), but with a 250Ah leisure battery – which will run continuously for weeks without intervention.

  14. What about using the powerpole at the outlet, then make your own standard electrical plug to powerpole adaptor. When the power goes out, change the light bulbs, add the adaptor and plug into the 12V circuit.

    This would prevent anyone from plugging into the 12V outlet by accident. As well as someone plugging your 12V lamp into a 120V outlet. The adaptor would be there to prevent it.

  15. Besides the danger of plugging a 12V item into a 120V line I think there could be danger in plugging a 120VAC device into 12VDC. Sure, 12 is much less than 120 but if the device uses a step-down transformer then to DC it would appear as a dead short!

  16. During an emergency I would think that having “normal” light fixtures operating would be a very low priority. Shaded fixtures waste light. I would just wire up permanent lighting with 12V LED strips in a tasteful way, stairs hallways bath kitchen as backup lighting for even sudden power outages yet alone the big one. This can be fulltime to nighttime lighting on a single circuit, dim ones in hall, bath, brighter ones outdoors.
    There is a lot you can do with 6 wires or less. I still run audio allover the house with the old phone wires in two pair of wires, gnd and two channels. I want to go quad.
    Just buffer the tape out of your main source with a small amp that’s clean. Set the volume modest for a half volt or so of output, leave the volume alone and run the end result into any stereo or powered speaker with its own volume pot and enjoy. The most independent system possible yet tied into central source.

    1. Actually lighting is a very low priority after the storm. You have no TV or internet usually so you just go to bed. Keeping the refrigerator and fans going are what you worry about after a hurricane. BTW did I mention I live in south florida and been there done that.

  17. I guarantee this would not meet code anywhere in the US and if you did have a fire, regardless of the reason, the insurance company would point to that as the source and say, “Claim Denied”.

  18. After going to all the trouble of installing this system, I think this bloke should be able to remember to think twice before plugging something into the sockets. Simply telling visitors “don’t use the sockets with “12V Solar” on them” should cover them too.

    Honestly, can’t someone have some confidence in themselves without everyone jumping on the “safety” bandwagon?

    Pah, anyway here’s one way to get some 12V LED light bulbs in standard fittings:

    See the second link for the conversion instructions.

  19. Just a suggestion for the “WTF” plugs, make one blade positive (say) the ground negative and fill the other blade hole with surgu (or whatever) and then cut the corresponding blade on the 12V plugs off, that way you really can’t plug one plug into the other and get power, that is if your too damn cheap to get different friggin’ plugs and outlets for 12VDC!

    1. The whole point to his setup was that he could use his existing light fixtures by changing to a 12 volt bulb and plugging into the 12 volt outlet. Trying to use on blade and the ground would defeat that purpose.

  20. I live in a cyclone area here in Australia, and have been considering a similar setup.
    However, my thinking is as follows:

    Lead acid batteries are messy and potentially dangerous and the cheap (standard automotive) ones do not like being discharged. Having said that, there are batteries out there that do not have the current capacity to start a car but will work in this situation quite well, and they are worth next to nothing. When they die from being discharged fully, just get more cheap ones.

    Plan B. is to scrounge an old HV battery from a hybrid car. Pairs of 7.2v modules in series to give a 14.4v supply, running equipment that can handle both 12 and 24v, and a DC-DC inverter for the stuff that doesn’t.

    Also, In the lead-up and post cyclone there generally not much sun around so I have decided to just charge the batteries from the mains.

    1. “Also, In the lead-up and post cyclone there generally not much sun around so I have decided to just charge the batteries from the mains.”
      Really? Post hurricane the sky is clear here. The Storm sucks all the water out of the air and you usually don’t have a cloud in the sky after the storm passes.

  21. In tropical North Queensland we get category 5 cyclones every few years (for reference, Katrina was only category 3). My solution to the 2-4 day power outages was just a bunch of 7Ah 12v AGM batteries which I would charge in advance.

    My friend however had a better solution since he would lose power for up to 2 weeks. He somehow get his hands on the fuel oil generator from a decommissioned warship (HMAS Adelaide I think). He and his neighbors would save old engine oil and cooking oil in a small silo for cyclone season. The difficulty was that all 10 houses on his subdivision had to have every appliance running to use the minimum output of a warship generator.

  22. Could hack a ‘box van’ have about 6 12v batteries in the cube get the mean green alternator, mount the 5000w inverter as well in the cube, add the outlet / usb combo into the cube usually passenger side, run the cube van a bit boom you have emergency power

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.