Minimalist lighting for long duration power outage - Page 1
Forum section: electronics / projects

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 01:17:31 am
content: This was originally a discussion from another forum about emergency light for power outage. A forum member there asked me to show some photos of my extended outage set up. Since they do not allow photo upload, so I decide to take the conversation about the photos over here to this forum.Attached are the pictures of my minimalist set up for long duration power outage emergency lights. The lights are not for "normal" few hour long power out, but for survival lights in long outages like the storm Sandy (11+days, no gasoline, no stores, roads closed for days) and the Halloween storm a couple of years before Sandy (8+days outage with 6-12 inch snow/ice). Sandy caused >30 days outage in some areas within 1/2 hour drive from my house. My solution is from my experience of Sandy and the Halloween storm. The solution is not high-tech butminimalist set up for endurance.[Photo 1]I have three people in my family, so my set up has three-count for everything. As these are for emergency, and I hate to put a lot of money into something that I hope I never touch, so they are mostly done with existing stuff I have at hand. The advantage is that since most are stuff I have at hand and are in used, so I know most of the stuff are in a working state.Along with lab bench testing, the solution was "field tested" with a 3-5 days outage and another outage of the couple-of-days type.(1) Eating/Cooking/Cleaning lightsOn the top right (photo1) are three RV/boat G4 ceiling lights wired to CLA (cigarette lighter adaptor) using 8 feet of speaker-wires. Note that they are "recovered" CLA from cell-phone chargers. I have a couple of splitters to allow 2 G4's to be connected to a CLA socket.Power come from a pair of typical car-starter/booster SLA packs each with built in CLA out, jump cable clip, and LED power indicator. The third one is a UPS type battery with CLA (5amp) attached.For "installing", I use painter's masking tape and tape it high up on the walls. Painter's tape gives me a very firm tape-down but can be easily removed with residue. Just one of this RV lights is adequate for cooking/cleaning/eating, but I usually use two to reduce shadows.(2) Since what gets me during the long outage is the total darkness, I what made I called my"Forever Lights". They are on the right of photo 1 -- Calling it Forever Light is easier than telling my wife to bring me that two-box-thing with the white plugs. They are on the right side of the photo - the ones with a pair of 2xAA case (with switch) Velcro back-to-back and with four LEDs wired as two pairs of two so it can aim in multiple directions.[Photo 2]Photo 2 has a better view of the inside of a "forever light" - and the Toshiba laptop power bricks for rapid charging.The "forever lights" are simple 3xAA ballasted to <10mA on low and 70-80mA on high switch selectable. Using a pair of 2xAA battery case velcro back to back, it takes 3xAA and the 4th slot is used for the ballast (trimpot/VR). The switch on the box with VR is On/Off and the switch on the other 2AA box is for Hi/Low. I keep 2 sets of Eneloop on stand-by for each of the 3 "Forever Light" - that is 18 cells in reserve. The silver batteries shown (in photo2) are Eneloop Glitter edition. At the start of an outage, I will be on my 20+ Energizers. I can afford to be lavish and set the LOW higher at 20mA. When I reach for my reserved Eneloops, that is the time when I lower the LOW to 10mA or below.Unlike store-purchased stuff, this is tuned forendurance. No led driver or anything fancy. No power wasted except to the ballast. Just a pair of these on HI would be adequate for cooking/cleaning/eating incase my SLA's are pooped. On 10mA LOW, a set of 3AA (2000mAH) would last at least 200 hours (current draw lowers as battery drains).(3)Since the CLA were recovered from phone chargers, the existing buck boards were remade (bottom of photo 2) asboost for the 3xAA packs to power the RV lightsin without dragging around the SLA's. This was initially targeted as (better than 2AA minimag) lighting for connecting up the SLA RV lights and for connecting the SLA for charging. But I found it useful for "in a pinch" or during early parts of an outage when I can afford to be lavish - making shaving a bit easier. I have since changed that to LM2577 boost, and housed them in clear (CamCorder) video tape box. This boost solution is kind of a5th wheeljust to give me options.Boosting is awful inefficientbut I kept it as option since it is already made. I have since added 18650 battery holders to them so I can use 18650 or my 3xAA. Recently I purchased some 18650 flashlights as replacement for my three 2xAA MiniMags. The 18650 flashlights will likely displace my boost solution is making less and less sense other than it is kind of fun to use. I like that wide spread light better than the battery's narrow beam. Very useful when I have to check under the hood of the car or look for something misplaced inside the car.(4)For no-rain no-snow fast-recharge, I use what I called"open-hood method"- I connected the two car-starter/booster jumper cable to the car AFTER the car is started and let it run for 15-20 minutes. That is enough juice to light the 6 G4's for a few days. While the car is running, all my CLA chargers can be working; and the CLA-to-CLA cable can charge my 3rd SLA from the CLA on the car jumper/booster pack.[photo 3](5) For fast charging during rain or snow(can't do the open-hood), I do what I called a "power visit". I drive to the library or coffee shop few towns away with power, or drive to the in-laws. I use my 15V 3Amp (and 15V 4Amp)Toshiba laptop power bricks converted to a CLA Voutplug and 5.1mm Vout seen in photo2. I can pump 3A into the SLA with the power bricks, and with a CLA volt meter, once the battery is back up to 14V (1-2hours depending on how low), I switch back to slow charging with the stock charger. At the in-laws, I use my CC/CV with my 19.5V brick and I can pump in 3A unattended. At the library, I cannot use my CC/CV boards (makes them nervous). I also don't use a DMM but instead a CLA volt meter for the same reason.Thewhite cable is a CLAwith both a male and female 5.1mm plug. The 5.1mm are used for RV/G4 as light splitter or as power-in for charging. You can see the CLA volt meter sitting on the white cable.To fast charge the 3xAA "forever light", I installed a power-out (white CPU fan socket/plug). When I am at a power-visit, I use my3xAA serial charge cable(lower right hand corner of photo 3,red+purple cable). They serialize all three packs and inside the pack, 3xAA serial. I use my 13.5V 800mA power brick to charge the 9AA in serial. Proven to be able to pump 600-800mA into the AA's. The "power visits" are shorter than the three+ hours it takes to fully charge an empty cell, so over charging is not a concert.(6) Lastly, both of my "normal" battery chargers are CLA enabled. The LaCrosse BC700 for NiMH, and the Opus BT-C3400 (Lithium, NiMH). I can connect them in the car while I am doing my "open hood" charging, or cross charge them from my SLA's.

author: Vgkid
author_rank: Super Contributor
timestamp: September 28, 2015, 01:37:20 am
content: Thanks for the post, it was informative.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 28, 2015, 02:33:51 am
content: You can use a stepper motor as a small generator. Just add a knob to make it easy to turn and you can run LEDs directly off it.

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 02:42:42 am
content: Quote from: NiHaoMike on September 28, 2015, 02:33:51 amNot too far from what I had to do.During Sandy, I was caught with my pants down. My 20+ AA's had a combined of about 1 to 2 hours on my 2AA MiniMag. (I had another 15-20 primary AA's, which at the time I couldn't find in the dark - the storage area was not bright even in daylight.).After that, I had to use the hand-cranked emergency radio with a lone LED light. By about the end of the first week, that crank handle broke.Since then, total darkness really gets me. So my #1 priority was to find some ways to avoid total darkness.

author: ez24
author_rank: Super Contributor
timestamp: September 28, 2015, 03:12:39 am
content: My max time was 5 days and it was not pleasant. My solution is I bought a D cell power LED lantern and always have a pack of D cells from Costco ( I buy one pack a year). I think it can go 12 hours on low.Plus I have dozens of AA batteries of all kinds and I guess by now dozens of LED flashlights.But I wish I had a house generator.We (in San Diego, CA, USA) just had a 1 1/2 outage at peak high temps and my dog came in from outside panting from the heat and screaming (he is a screamer) from the heat. I had to give him ice baths. SO anyway a 12v battery fan is in my Amazon cart now.Buying a pack of batteries once a year from Costco is not too much of a burden.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 28, 2015, 04:33:43 am
content: The nice part about the stepper motor generator is its simplicity. No batteries of any kind to maintain and really not much to go wrong.In my experience, the three cell flashlights will stay lit far longer than most two cell flashlights as they just have a simple resistor or at most a LDO controlling the current, not a boost converter that tries to hold a constant brightness.

author: mzzj
author_rank: Super Contributor
timestamp: September 28, 2015, 06:55:17 am
content: Quote from: Rick Law on September 28, 2015, 01:17:31 amIn extreme cases you can get along with truly microscopic power. I can read a book with one cree XM-L led running at 20uA. Powered with 3x energizer AA lithiums that will give you a 20 year runtime.Need something more powerfull to find the book though.I have been also thinking of survival in similar situations but for me the heating would be a number 1 problem. In summer we don't need heating or lightning, just shades to block the light when we sleep...For heating we rely on electricity. Fireplace is mostly unused and I think I would have enough firewood for 4 days tops. Luckily we don't have bad snowstorms, 1 day road blockage would be already exeptional.

author: con-f-use
author_rank: Unknown
timestamp: September 28, 2015, 01:51:38 pm
content: Lanterns and (more so) candles are a fire hazard, especially in an earthquake.

author: Fungus
author_rank: Super Contributor
timestamp: September 28, 2015, 02:06:36 pm
content: Quote from: mzzj on September 28, 2015, 06:55:17 amIsn't that what clothes are for?As for lighting: You can buy big boxes of batteries.Those LED headlamp things usually have a low power mode that lets them go for hundreds of hours.eg. Random web search gives:http://www.outdoorgearlab.com/Best-Headlamp- 200 hours lifetime? No problem.One of those and a big box of batteries could keep you going for years.

author: djQUAN
author_rank: Frequent Contributor
timestamp: September 28, 2015, 03:00:11 pm
content: We have a 1kW off grid system at home so power is not really an issue during outages. But if necessary, or when I need power away from home, I made this.It uses twelve 15Ah LiFePO4 cells wired for 12.8V 45Ah,built in 3a solar charge controller. Two outputs (one 15A cig lighter, one 15A binding post)all inside a waterproof Pelican clone case.An external 40W folding PV for recharging.I can use an external inverter or use DC directly.I use it everyday for a DC electric fan and charging my flashlight or bikelight battery pack just so it gets used (get back some of the money I spent on it, PV sits on the roof) and is often kept at or near 100%SOC for emergencies.

author: Lightages
author_rank: Unknown
timestamp: September 28, 2015, 03:23:47 pm
content: With the price of small solar chargers now, what is the point of disposable batteries? If there is a local disaster that takes out the grid for a long time, good luck finding fuel or batteries. It is much better to have self renewable energy like solar cell chargers and/or hand cranked generators. It is cheaper in the long run too. Martin Lorton has been doing some extensive tests on solar charter packs.I have a 3kW of solar panels, 24kWh of batteries and a 4500W inverter. The batteries are near the end of their life but I have another year with them. New AGM batteries with my use last around 6 years. I think that is the best way to ride out local power problems. I don't have any!

author: ez24
author_rank: Super Contributor
timestamp: September 28, 2015, 05:37:39 pm
content: Quote from: wilfred on September 28, 2015, 07:06:11 amWhen they burned down everything they were in.

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 06:26:09 pm
content: Quote from: ez24 on September 28, 2015, 03:12:39 amIn the case of Sandy, it was no help since gasoline was not available in the area. Per overhearing a stranded motorist call to AAA (Auto club). Closestconfirmed availabilityof gasoline was 40+ miles away.That aside, as it turned out, most of those generator are not "simply pull out on emergency and off you go." The generator needs to be drained and cleaned after use, or run once a month to avoid the clog. I don't have one so I cannot confirm the details; but My in-law got caught with that problem during a different outage - the darn thing wouldn't start because of improper preparation prior to (re)storage.Advice from other is, apart from emergency fuel, keep a can of carburetor cleaner with the "emergency kit."

author: dom0
author_rank: Super Contributor
timestamp: September 28, 2015, 06:38:38 pm
content: Quote from: mzzj on September 28, 2015, 06:55:17 amIn some circuits I use LEDs to bias stuff and I'm always surprised how bright some LEDs are, even when they're just running at micro-watts.

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 07:02:31 pm
content: Quote from: Fungus on September 28, 2015, 02:06:36 pmre: (mzzj I have been also thinking of survival in similar situations but for me the heating would be a number 1 problem.Now that I have lights, heat is my main concern. Lucky for me, my natural gas works. Cooking and oven baking gives me some heat but hardly enough.re: "Isn't that what clothes are for?"Clothing solves the problem part way, but house freezing causes other problems. Apart from cracking wall joints and other annoying thing, the worst is frozen water pipe. I just finished repaired/repainted the dry wall thus completed the repair of frozen pipes from another (winter before last) 5+ days power outage. The burst fixed was done shortly after the outage, but I stopped before the wall finishing just so I can check if my repair survived a full freezing winter before I close up the wall.Words from just one single experience: The burst may not become apparent when it froze. It was when it melts. When warmth return and the melting of the frozen pipe eventually melt to the burst part and broke the ice-plug. I heard this BANG! Then another...Another interesting thing: Finding where it broke inside the dry wall was hard. The wire/pipe detection tools from home depot didn't work since the pipe was on the far-side of the dry wall. It gave me positions that is obviously wrong. It occur to me tofind the wettest part using my DMM. That works! I narrow down to the (biggest) burst to within 2 inches using my UT-61E.re: As for lighting: You can buy... ... ...Part of the fun of being an EE-hobbyist with is to make useful things. So I took that opportunity to get some self gratification.

author: mzzj
author_rank: Super Contributor
timestamp: September 28, 2015, 07:14:48 pm
content: Quote from: Lightages on September 28, 2015, 03:23:47 pmSo you would recommend renewable solar power for backup use in case of snowstorm or hurricane?Up here we wont get much sunshine in winter months or if at all. Snowstorm wouldn't make it any bettter.Fungus:Yeah, I can keep myself alive but like Rick already said freezing pipes are a problem. Not a life-threatening problem but very expensive though.I Have undo jacket + extreme weather undo sleeping bag and I am probably good down to -30 degrees.But have 800++ meters/yards of plastic pipe inside the concrete floor slab and I wouldn't like if it freezes and breaks!

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 07:19:48 pm
content: Quote from: Lightages on September 28, 2015, 03:23:47 pmNot very useful during winter. During winter outages, houses with the solar panels are as light-less as the one next to it.It takes many days of sunshine to melt the roof ice/snow. A few inches of snow can leave the roof top covered for weeks or months. During the Halloween storm, it started with 6-8 inches of snow. The snow-ice-snow layers took months to melt. Sandy didn't start with that much snow but enough to "fully cover". It was also followed by cloudy days, so for weeks, what was on the roof stayed there.I did consider a small mobile panel - one that I can keep indoor and take out when the sun is out. But back-of-envelope evaluation is that I wont be able to charge much of anything with a small panel under that limited winter sun.

author: mtdoc
author_rank: Super Contributor
timestamp: September 28, 2015, 07:32:51 pm
content: Quote from: Rick Law on September 28, 2015, 07:19:48 pmNot true. Unless one lives above the Arctic Circle - winter sun produces real power even for those in the snow belt. Snow can be brushed off of panels (I do this)I know people who live in Canada and the Northern US who tilt their panels vertical and facing South in the winter. Snow does not accumulate on the panels and they benefit from reflection of light off of snow.In most places snow storms last a few days at most and are generally followed by clear, cold days - ideal for producing solar power. As long as your battery bank is large enough (or you have a generator or wind or hydro) you can and should (if your system is properly designed) be able to tolerate a few days without sun.Solar panels are so cheap now many people are over-sizing their arrays - specifically to provide sufficient power regardless of the length of the day or cloudy skies.

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 07:45:52 pm
content: Quote from: mzzj on September 28, 2015, 07:14:48 pmI can attest to that! Not just the pipe itself but the damages it caused. Just one bloody meter/yard of pipe with 3 burst! Very expensive indeed and lots of work.

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 07:49:41 pm
content: Quote from: mtdoc on September 28, 2015, 07:32:51 pm

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 07:59:11 pm
content: Quote from: mtdoc on September 28, 2015, 07:32:51 pmMost solar panel in my region are not vertical but fix-mounted on roof tops. Most roof tops in my area are 2+ floors above ground.Mine is 3 floors (35-40 feet-ish) since the basement is mostly above ground. I can't even get to my gutters to clean it let alone getting all the way to the roof to brush off anything. Most of my neighbors are in similar situation.In this region (New Jersey), the solar panel equipped houses are as light-less as the one next to it during a winter outage. The only houses with light come with the audio confirmation of a running generator.

author: mtdoc
author_rank: Super Contributor
timestamp: September 28, 2015, 08:04:58 pm
content: The vast majority of residential solar installations are strict grid tied. Summer or winter - when the grid is down - they have no power.

author: Fungus
author_rank: Super Contributor
timestamp: September 28, 2015, 08:25:57 pm
content: Quote from: mzzj on September 28, 2015, 07:14:48 pmInstall a tap to empty it?

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 08:47:38 pm
content: Quote from: mtdoc on September 28, 2015, 08:04:58 pmThen what is the point of suggesting it as a backup to the grid?[Edit: removed - it sounds too combative.]Then for sure it is not appropriate to use as backup to the grid.

author: mzzj
author_rank: Super Contributor
timestamp: September 28, 2015, 08:50:38 pm
content: Quote from: Fungus on September 28, 2015, 08:25:57 pmI guess you have never seen underfloor heating system manifolds?

author: mtdoc
author_rank: Super Contributor
timestamp: September 28, 2015, 08:58:37 pm
content: Quote from: Rick Law on September 28, 2015, 08:47:38 pmIf you're referring to Lightages post, he specifically mentioned his solar PV system with batteries and inverter - i.e. - NOT strict grid tied.I have what's called a "Grid tied with battery back up system" myself. I have 4500 watts of PV and 20 kWh of battery storage - enough to run everything but heat in my home for 2 days without sun.Many people have similar battery back up systems (or are off grid). Some have small systems only for minimal lighting, refrigeration, etc - others may have systems to back up everything. These systems if properly designed, will supply enough power to see one through grid outage during a winter storm. In fact in my case that is the main reason why I installed it in the first place - since we see outages during the winter for up to a week. Just fire up the wood stove (which is usually going in the winter anyways) and business as usual. It's great to have uninterupted power when others are firing up generators, using candles, etc

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 09:08:15 pm
content: Quote from: mtdoc on September 28, 2015, 08:58:37 pmOur post crossed. I just reworded it as you post, I guess. I reworded the "what is the point..." since it sounded so combative. I reworded it to "Then for sure it is not appropriate to use as backup to the grid."What you suggest may well work, for a while. I am talking about extended outage of over a week. For that to work, you will need major investment in battery. Since battery is a consumable, that would be a recurring expense.

author: AG6QR
author_rank: Frequent Contributor
timestamp: September 28, 2015, 09:14:00 pm
content: Quote from: mtdoc on September 28, 2015, 08:04:58 pmYou're right about the vast majority. But people on this forum should know how to do better than that. The grid tied systems are, of course, designed for most economical energy production during normal circumstances. But it shouldn't be hard to get a little bit of emergency backup capability for times when the grid fails. It's easier if you "think lifeboat, not cruise ship" -- in other words, don't worry about the hot tub and the big screen TV, but just try to maintain some minimal capability for safety and comfort.I've been considering adding a small RV-style 12V system to my house. A simple deep cycle 12V battery, about 100Ah or so, either AGM or flooded, with a small solar panel on the roof to keep it topped off, should be enough to make life less uncomfortable for an extended outage. It could power some LED lights directly, as well as being able to power some small AA/AAA battery chargers for various small devices like flashlights and radios (I've already got a couple of Maha 204GT battery chargers that run directly off of 12V). It's easy enough to find 12V chargers for cell phones and such, but the cell network may not be working after the kind of disaster that brings down the power grid. I also have ham radio gear that I'll be using if we have an extended outage. My radio gear is mostly fairly low power, running off 12V directly.In my area (north of San Francisco, CA) we don't worry about snow or freezing pipes, and even in the depth of winter, we can survive without space heating, though we'd need to wear coats. We do have occasional winter rainstorms that can knock lots of trees down at once, damaging the power grid, and we also have the ever-present threat of earthquakes. In the time I've lived here, I've had week-long outages twice, both in mid-winter.I've already got a 12V lighting system in my camping trailer, along the lines of what I'm thinking about for home, except that it's charged by my vehicle while I'm towing the trailer, instead of solar.For 12V lighting fixtures,http://led4rv.comis one source that I've been pleased with.One suggestion for the devices in Rick's original post: for 12V power outlets and connectors, consider Anderson Power Poles instead of cigarette lighter plugs. They're more compact, less prone to spontaneously disconnect, and capable of higher currents. One source ishttp://qsradio.com.

author: mzzj
author_rank: Super Contributor
timestamp: September 28, 2015, 09:31:58 pm
content: Quote from: mtdoc on September 28, 2015, 08:58:37 pmWell.. skip the solar panels and just trickle charge that huge battery from grid.And a 20 kwh battery is bit different calibre of solution compared to thread starter. 50 dollars to flashlights vs 2000...6000 dollar investment to 20 kwh battery bank. Heck, you can buy 10000 AA alkalines with that money.--Modern diesel cars are reasonably efficient at idle compared to small cheap gasoline generators. My diesel van would run 90 hours on full tank and provide possibility to charge other 12v batteries. Probably has empty tank if needed.-- for cold winter climates thermoelectric generator would be a neat solution. 100watts out of wood heating stove should be possible.

author: mtdoc
author_rank: Super Contributor
timestamp: September 28, 2015, 09:47:18 pm
content: Quote from: AG6QR on September 28, 2015, 09:14:00 pmThis is a good solution for minimal lighting, cell phone charging, etc and more in line with the OPs expressed need.For example, I have a large shed with it's own power system - 1 12 V 80Ah deep cycle battery, small charge controller and one 145 watt solar panel. Total cost - about $300. This is enough to power several LED lights for several days without sun.It's all about calculating expected loads and designing a system around that.Rules of thumb:Calculate 24 hr load (in Wh's)Have enough battery storage to run loads (with no sun) for at least 2 days without discharging battery below 50% SOC.Size battery accordingly. ---> eg - if 100 Wh daily load - battery needs to be have at least 400 Wh capacity. For 12V nominal battery that means at least 33 Ah (20 hr rate).Size panel to provide charge rate of at least 10% of battery capacity (20 hour AH) when in full sun ---> eg - for 100AH 12V battery - 12 V nominal PV panel should provide at least 10 amps when in full sun. (Assume real world PV panel output of about 80% of STC rating).

author: Lightages
author_rank: Unknown
timestamp: September 28, 2015, 09:56:40 pm
content: Oh c'mon people! The post is about minimal lighting for long periods of power outage. I suggested that small solar chargers and/or hand cranked generators would be a better bet than stock piling disposable batteries or trying to find more when they run out. This is my suggestion, not a full blown solar system. That was just used as an example of the other extreme. It amazes me when people always read what they want instead of what was written. I even do that sometimes.

author: fivefish
author_rank: Frequent Contributor
timestamp: September 28, 2015, 10:01:03 pm
content: Batteriser

author: mtdoc
author_rank: Super Contributor
timestamp: September 28, 2015, 10:02:51 pm
content: Quote from: mzzj on September 28, 2015, 09:31:58 pmOf course! I was just responding the the post that claimed using solar power to charge batteries during winter was not possible (as Lightages had suggested). The discussion diverged. Big deal. Of course a large PV system was not being proposed to solve the OPs need. See post above.

author: Deathwish
author_rank: Unknown
timestamp: September 28, 2015, 10:26:27 pm
content: I have a hand crank led lantern and a handheld hand cranking torch. If I need to get about , sod it I will be knackered unless I get a sledge and some huskies.

author: Stupid Beard
author_rank: Regular Contributor
timestamp: September 28, 2015, 10:45:41 pm
content: I use a combination of candles and LED torches. Candles for general background lighting, and an LED torch for walking around with if i need it. Mostly I just let my eyes adjust and do without light unless I really need it.Actually, I have about a kg of wax and a load of wick so if I run out of candles I can just make more. Which has the added bonus of giving you something to do in a power cut. As long as I don't run out of gas for the gas stove anyway, which would be a tragedy as I'd not be able to make more tea.Hmm. On second thought, maybe I wouldn't bother with making more candles. Tea is much important than lighting.

author: Rick Law
author_rank: Super Contributor
timestamp: September 28, 2015, 10:47:17 pm
content: Quote from: AG6QR on September 28, 2015, 09:14:00 pmI think this is a great analogy. The discussion diverging is, I suppose, to be expected.Just as the thread in another forum, the discussion quickly divided into "cruise ship" vs "lifeboat."Anyhow, as the title suggest, mine was a minimalist solution for "survival lighting." I suppose I am guilty of impatience since all the "big solutions" was discussed at least once in the other forum.

author: Stupid Beard
author_rank: Regular Contributor
timestamp: September 28, 2015, 11:16:04 pm
content: Quote from: Rick Law on September 28, 2015, 10:47:17 pmI think people just have different levels of what they are willing to put up with and there's only a limited number of ways you can make light.You stated in your first post that you don't like the dark. In my case, Ilovethe dark and I would be perfectly happy without any artificial lighting at all. Clearly no solution that I come up with for myself would be one that you'd be able to live with, and anything you came up with would be luxury for me.

author: Rick Law
author_rank: Super Contributor
timestamp: September 29, 2015, 02:16:48 am
content: Quote from: Stupid Beard on September 28, 2015, 11:16:04 pmI used to not mind the dark. During Sandy, the total darkness really got to me. I think it is the multi-factor of dark and quiet and cold. Lacking the typical humming of the refrigerator (and other stuff), and cold, and then the total darkness. After about 3 or 4 days, I hated it. I would go into the garage (where I hid from my kid to smoke) andstrike a match just to see some light.I think my lighting is adequate for my taste now. The no-heat problem is the front page now. With all the new stop-valves I installed (with drain caps), frozen pipe,I hope, will be a thing of the past.

author: DanielS
author_rank: Frequent Contributor
timestamp: September 29, 2015, 03:54:47 am
content: Quote from: Stupid Beard on September 28, 2015, 11:16:04 pmI generally do not mind total darkness if all I am going to do in it is sleep.If I need to get up to go to the bathroom though, it can be very inconvenient and potentially painful: the way my apartment is setup, the hall connecting the front to the back is offset several meters from any window and becomes extremely dark at night even with street lights still on, which caused me to smash a hand or foot in the partially closed bathroom door I could not see a few times. I had to install a 1W night light in the hall to fix that, which also provides just enough light around the door to let me see my shoes and slippers when I get home at night without having to walk across the kitchen to turn on the lights.Getting home on a clear new moon night (no moon and no clouds to reflect light from elsewhere) during a power outage with no backup lighting would be very annoying.

author: Fungus
author_rank: Super Contributor
timestamp: September 29, 2015, 05:08:53 am
content: Quote from: DanielS on September 29, 2015, 03:54:47 amLack of practice.Quote from: DanielS on September 29, 2015, 03:54:47 amStarlight? You might be surprised what your eyes can do if you just give them a chance...(Unless you suffer from night-blindness in which case I'll let you off)

author: Rick Law
author_rank: Super Contributor
timestamp: September 29, 2015, 05:21:23 am
content: Quote from: Fungus on September 29, 2015, 05:08:53 amAwww... Give him time, by the time he is over 50, he will get to practice every 60 minutes.A wise man once told me: "When you are over 50, never pass a bathroom by without using it..."

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 29, 2015, 05:25:45 am
content: Quote from: Rick Law on September 28, 2015, 07:02:31 pmAgain overthinking the solution to the problem. All you need is to turn off the water and then use a bicycle pump to blow out the pipes.For that matter, a stationary bicycle generator (or a bicycle with a stand to allow it to be used as a generator) will easily generate about 100W or so, which is a lot for powering portable electronics and LED lighting.

author: frostheave
author_rank: Contributor
timestamp: September 29, 2015, 05:57:23 am
content: Quote from: fivefish on September 28, 2015, 10:01:03 pmNicely Done!

author: Fungus
author_rank: Super Contributor
timestamp: September 29, 2015, 06:48:26 am
content: Quote from: frostheave on September 29, 2015, 05:57:23 amI've been trying not to post the word "Batteriser" in this thread for a couple of days now...

author: mzzj
author_rank: Super Contributor
timestamp: September 29, 2015, 06:56:15 am
content: Quote from: Lightages on September 28, 2015, 09:56:40 pmI just don't see the point of solar part, trickle charger will do the same for me. But it really depends on the location and type of problem/catastropheSolar panels and rechargeable batteries are good option if you live in a country with frequent power outages but then it's more a daily life than "catastrophe"Snowstorm in Anchorage, not so good.And piling disposable batteries is not necessarily so expensive or troublesome compared to solar+SLA battery:Good quality 100Ah solar battery cost around 300eur/usd and is rated for 10 years. Personally I woudn't necessarily rely on it for more than 7 years. Would be about 1,2kWh of energy.For same energy content you need somewhat crazy amount of AA batteries but just for kicks: 3Wh per cell, 400 pcs needed. Good quality panasonic cells with 7 year self-life from digikey: 0,25eur per piece, 100 eur total.For sure running a inverter or anything like that from 100Ah solar battery is easier, but if you really need you can even run a angle grinder with AA-batteries.

author: Fungus
author_rank: Super Contributor
timestamp: September 29, 2015, 07:25:45 am
content: Quote from: Rick Law on September 28, 2015, 07:19:48 pmWind? That will work in the worst blizzard.

author: Smokey
author_rank: Super Contributor
timestamp: September 29, 2015, 08:06:26 am
content: Quote from: Fungus on September 29, 2015, 06:48:26 amBut what good is that clapping money going to do you in an emergency???Honestly though, if you live in an area where you essentially know there is going to be a big weather disaster every couple years (I'm looking at you Florida/Louisiana) is there any excuse not to have a generator and a fuel supply ready in the bad weather seasons? Forecasts are pretty good at giving you at least a day notice before it gets really bad. It's not like earthquakes that come out of nowhere.Here are some alternate sources of electrical generation anyway:http://www.rei.com/product/872900/power-practical-powerpot-v-recharging-cook-pothttp://www.rei.com/product/846334/biolite-wood-burning-campstovehttp://www.econvergence.net/The-Pedal-A-Watt-Bicycle-Generator-Stand-s/1820.htm

author: DanielS
author_rank: Frequent Contributor
timestamp: September 29, 2015, 02:35:44 pm
content: Quote from: Fungus on September 29, 2015, 05:08:53 amNo amount of practice is going to save my toes from smashing into a half-open bathroom door if I assume that the door is open because I did not find the handle anywhere near the closed position.Quote from: Fungus on September 29, 2015, 05:08:53 amIf the hall is already nearly pitch-black with sodium street lights that are orders of magnitude brighter than any visible star and have a much more direct entry angle through windows, starlight is not going to help me indoors. Outdoors, I would likely be stepping out of the car after getting repeatedly blinded by oncoming traffic headlights, looking at the road ahead of me lit up by my own headlights and all the dash lights for some number of minutes before getting one final blast of cab lights when I open the door, so it may take a while for starlight to become useful.

author: Chris C
author_rank: Frequent Contributor
timestamp: September 29, 2015, 03:04:05 pm
content: Quote from: Rick Law on September 28, 2015, 01:17:31 amI couldn't determine the nature of the "ballast", but if it's resistive or a linear regulator, then the amount of power wasted can be significant. Maybe the amount of resistance or voltage drop is minimal in your case. But I think you'd get better overall endurance from a single larger and higher efficiency brand-name LED like a Cree, with a proper driver.I have some remote phosphors from Intermatix, used to convert royal blue light to white. Used properly, they're supposed to have even better efficiency than white LEDs with integrated phosphors. That may be optimistic for DIY. But even if they provide the same efficiency, they still by nature produce a nice, diffuse light source. Just waiting to get some time to play with them.Still, it's a very useful project. I got caught pants-down with hurricane Gustav, and wish I'd had something like this. I got by by strapping the only LED flashlight I had at the time to a baseball hat. So at least where ever I went, I had light.

author: Rick Law
author_rank: Super Contributor
timestamp: September 29, 2015, 05:56:17 pm
content: Quote from: Chris C on September 29, 2015, 03:04:05 pmYes, it is a pure resistive ballast with a trimpot VR. Since my goal is 5-10mA consumption on LOW, I can't find any LED driver that would output 10mA range, and many of the without-boost types driver aleady consume 1-2mA by itself. Gut feel from working on other booster, the boost types is going to chew up 30% to 40% waste. Yes, the resistive ballast waste is high, but total waste (WH or mAH) is lower than alternatives I can think of. (Suggestions welcome).I still experiment with those 3AA "forever lights". I installed a 18650 battery protection circuit to use the 2.6V cut-off at to prevent reverse charging. But I am of two minds - should I trade the death of a few Eneloop just for a few more hours of light? (Suggestions/arguments welcome)As to converting blue light to white, I am not using blue LED. The LED I use are ultra-bright cool-white (6500K). My lighting perception is "it seems to light better" at 5000K and up. I didn't want to diffuse by passing it over filter (or mirror) since the light is already too low as it is. I install it as 2 pairs of 2 so I can point it at different directions. The pairing is "in case one fails" since repair (soldering) will have to wait till power returns. They are so under-driven that they should last except for manufacturer's defects.I think simplicity (of deployment) is important - Long power outage is stressful. So, to make it simple with "what to hand to whom" from the emergency box, I use different color for heat shrink tubing. The ones is blue are assigned to me, red is for my wife, and yellow is for the kid. Same for the Eneloops - black (glitter edition), (gitter edition) silver, and white-taped covered. A bit silly-extreme perhaps...

author: mzzj
author_rank: Super Contributor
timestamp: September 29, 2015, 06:52:11 pm
content: Quote from: Rick Law on September 29, 2015, 05:56:17 pmYou might have to roll your own drivers for best efficiency at 10mA. Plenty of candidates, 95% efficiency should be doable but not trivial.I am not sure what led boards you are using but it looks like cheap &chinese. Can be anything 20...100Lumens/watt. State of the art led's from Cree or Lumileds should give you over 170Lumens/watt, 200 Lumens/watt might be within reach if you oversize your led power ratings by 5-10x

author: Someone
author_rank: Super Contributor
timestamp: September 30, 2015, 01:23:19 am
content: Quote from: Rick Law on September 29, 2015, 05:56:17 pmThere are many low power boost converters that can be setup for running LEDs at low currents, current limiting in the switch helps with a good control loop design. A simple design with a power oriented AVR could be a good start for a rough regulator but a well tuned continuous time design will be better in all areas.

author: djQUAN
author_rank: Frequent Contributor
timestamp: September 30, 2015, 01:41:07 am
content: Quote from: Chris C on September 29, 2015, 03:04:05 pmHere is something I did with remote phosphors when we had a 3 day power outage last year.http://laserpointerforums.com/f66/experimental-remote-solid-state-lighting-89708.html

author: Chris C
author_rank: Frequent Contributor
timestamp: September 30, 2015, 03:49:42 am
content: Quote from: Rick Law on September 29, 2015, 05:56:17 pmThe idea was that a single, large, high-efficiency LED could show efficiency gains ofmorethan 30-40% over the generic 5050 LEDs on your boards. And then, because it's a single LED, you could use a more efficient buck as well, instead of a boost. So even though the electrical losses would be higher than in your current scheme, the light output per watt and longevity would still increase.

author: Chris C
author_rank: Frequent Contributor
timestamp: September 30, 2015, 03:55:45 am
content: Quote from: djQUAN on September 30, 2015, 01:41:07 amWow, that's some brilliant light! Probably exceeding the limits of the phosphor, in which case you'll get more light by defocusing the laser. I did test with a laser, but it was a much lower-powered one.Regardless of whether I used a laser or a LED, I noticed the spectrum of emitted light changed depending on which side of the phosphor it struck. Which is odd, because the datasheet doesn't mention anything about there being a front or back. Were you using an Intermatix phosphor, and did you notice anything similar?

author: djQUAN
author_rank: Frequent Contributor
timestamp: September 30, 2015, 04:08:42 am
content: Quote from: Chris C on September 30, 2015, 03:55:45 amThe laser is multimode so the beam spreads at distance. It is indeed defocused a bit so at that distance, the "spot" is actually a square.I can't recall where I have seen it but the Intematix phosphor mentions the matte side faces the light source. And indeed, the light color and output is better following that.The matte side is where the phosphor coating is. If you put light on the wrong side, the resulting output is more bluish and unnatural.

author: mzzj
author_rank: Super Contributor
timestamp: September 30, 2015, 06:24:02 am
content: Quote from: Chris C on September 30, 2015, 03:49:42 amI woudn't be suprised if there is 4-10 times better efficiency with good LED compared to those 5050 Led boards. Some of those 5050 led boards just plain suck in my experience.Potential 400%-1000% gain on light output or runtime sounds like worth of some trouble.

author: Rick Law
author_rank: Super Contributor
timestamp: September 30, 2015, 05:02:25 pm
content: Quote from: Chris C on September 30, 2015, 03:49:42 amQuote from: mzzj on September 30, 2015, 06:24:02 amI have been thinking about that too. The 5050 LED lights are RV ceiling lights powered by SLA (within the car jumper/booster pack) is planned to be re-charged by the car during power out. 20 minutes car-recharging will store enough in the SLA to run the RV lights for a few nights. Since gasoline outage like Sandy is rare, that is low on my list. That said, I am kind of working on that. I got some 1/2 Watt LEDs planning on running it as 3 in serial plus a simple resistive ballast. I have not considered buck board for that. I should re-think that one.The boost (with 1x18650) for the RV ceiling light is kind of a 5th wheel that is more for fun than real use - particularly since now I have 18650 flashlights giving me better lighting than the 2xAA MiniMag for "hooking up stuff" at the start of an outage.Higher on my list of improvement is the 3xAA 4-LED light I rely on for really bad extended outage. The 4xLEDs powered at combined 10mA at LOW and 80mA at HIGH. Right now, these are simple resistive ballast using trimpot to trim to 8-10mA. Those are the ones I like to make as efficient as possible. They are 200 hours per set of battery right now. Initially, I tried to buck down the 3AA to 2.xV-ish for LOW using the MC34063A. That damn bucking burned >5mA by itself so I abandoned that. I wouldn't mind finding a more efficient way.

author: DanielS
author_rank: Frequent Contributor
timestamp: September 30, 2015, 07:32:52 pm
content: Quote from: Rick Law on September 30, 2015, 05:02:25 pmWhat you should be looking at is "micropower buck regulators" like these:http://www.linear.com/parametric/Micropower_Buck_RegulatorsQuite a few models can drive 100mA or greater outputs with quiescent current under 100µA. Since using three cells with a buck regulator only allows you to drain them down to 1V per cell when using white LEDs, you might want to go with four cells so you can drain them to 0.8V or less. With something like the LT3103, you should be able to get ~92% efficiency across the 5-80mA range and achieve around 400 hours per set of four cells when driving the LED at 30mW "low" setting.

author: Rick Law
author_rank: Super Contributor
timestamp: September 30, 2015, 09:04:15 pm
content: Quote from: DanielS on September 30, 2015, 07:32:52 pmThanks, DanielS , great suggestion! I didn't even know there is a whole category of "Micro Power Regulator". Their efficiency is much better than I expected as well. I should get a few next time I order something!

author: sarepairman2
author_rank: Frequent Contributor
timestamp: October 01, 2015, 02:48:30 am
content: I was out of power for a week.Luckily I had a generator that I purchased for maybe 400$ that ran my whole house on a week.It's really not that expensive or hard to run a generator.Are you guys in some area that generator noises attract zombies?Every solution in this thread seems inferior to just.. buying a home depot generator!

author: Rick Law
author_rank: Super Contributor
timestamp: October 01, 2015, 04:07:45 am
content: Quote from: sarepairman2 on October 01, 2015, 02:48:30 amIt is not the expense.Long winter outage at times interrupts gasoline supply. During Sandy, there was no gasoline. Roads were out, bridges were out. First night, I heard the sound of generators in the neighborhood. By second night, it was all quiet.4 or 5 days after the storm pass, road condition eventually permit me to get to a near-by town with electricity. At the coffee shop recharging, I overheard a stranded motorist's call to the motor club (AAA), the nearestconfirmed gasoline availability was in a town 40+ miles away. That couple didn't have the gas to get there.For over a month, I was filling up in another State after my in-laws (who lives there) scouted which station has gas and is open for business for that particular day. That was a 3 hour drive round trip just to get some gasoline.Consequently, my emergency plan excludes gasoline powered generator. There aregenerators designed to use natural gas. One of my friend has that installed post Sandy.

author: DanielS
author_rank: Frequent Contributor
timestamp: October 01, 2015, 06:45:57 am
content: Quote from: sarepairman2 on October 01, 2015, 02:48:30 amI live in an apartment. I have nowhere to put away a generator when not in use and no way to conveniently, legally or safely connect it to building wiring. My mother owns a house with a garage and a generator but if I owned the house, I do not think I would like to waste floor space on a generator I might use maybe once every other year.Also, running a generator for backup lighting would be horribly wasteful, not worth it unless you need it for other reasons, such as freshening the fridge and freezer, cooking, central heating, recharging everything that can be, etc.The only truly major outage I have experienced was an ice storm in 1997. Tons of streets, roads and highways were closed due to downed power lines and my apartment had no power for nearly two weeks, so I stayed at my mother's house through most of it. She had to drive an hour out of town for the first few days to get gas since local stations were either closed (no power, damaged/unsafe or buried under a 20-30cm thick layer of ice) or were sold-out nearly as fast as tankers could get to them because people were tailing tankers to stations in a bid to be among the first in line wherever they went. It was an "interesting" experience.An SLA with some white LED strips would have been nice to have for night lighting between generator runs back then. 20-30 minutes of charging while running the generator for other reasons would have provided hours of backup lighting.

author: mzzj
author_rank: Super Contributor
timestamp: October 01, 2015, 07:28:37 am
content: Quote from: Rick Law on October 01, 2015, 04:07:45 amIf you have large natural gas or LPG tank for heating you should definitely get a generator that runs on it. I think there is conversion sets for some generator models and if you have no other option you can probably rig up something. Of course the generator is not an replacement for all these battery powered lights, you still need battery powered flashlight when you fix than damn fine generator in a snowstorm!This side of pond we don't have gas tanks, but some houses have oil burners and 2000-3000L oil tanks. You just need a diesel generator in that case, bit more expensive (and usually also more durable).We have had couple of bad winters recently on the rural areas, usually its the farmers that are suffering when they would need to milk 300 cows and milking machine runs on electricity. I think in here farmers are using generators coupled to tractor PTO shaft instead of standalone gensets.

author: Rick Law
author_rank: Super Contributor
timestamp: October 01, 2015, 04:58:52 pm
content: Quote from: mzzj on October 01, 2015, 07:28:37 amA week ago, my thought would have been "for something that only hits once every few years, do I really want to spend that much?" But since we are all hype by acoming storm starting this weekendand a smaller storm expected for tonight, my thought is "may be I should have..." Just now on the radio, a "state of emergency" has been declared by the Governor of the State (NJ) as of this morning.Probably nothing again, but now the action list:>> Go to bank, get cash (ATM/Credit Card didn't work during Sandy)>> fill up the car!>> recharge all batteries... ...I am luckier than some, our natural gas pipes are underground and I had no natural gas outage since I moved here. During every power outage, I always have hot water since the water heater doesn't require electrical power. The natural gas generator would keep my natural gas heating system running, but needs to be wired by licensed personnel.The 3xAA based LED's (that I optimistically call "Forever Lights") gives me a sense of stress relief that is far beyond its value. I know I will have some light, however little. I was thinking LDO - now that I know "micro powered buck switcher" exist, I surely will experiment with that if just for the fun of it.

author: DanielS
author_rank: Frequent Contributor
timestamp: October 01, 2015, 05:20:38 pm
content: Quote from: Rick Law on October 01, 2015, 04:58:52 pm* foreverness intensifies ** the foreverness has been doubled! *

author: Rick Law
author_rank: Super Contributor
timestamp: October 01, 2015, 05:40:53 pm
content: Quote from: DanielS on October 01, 2015, 05:20:38 pmre:"... gives me a sense of stress relief ..."Actually, I used the wrong word. "stress relief" is the wrong word - should be "peace of mind".re "foreverness intensifies/the foreverness has been doubled!"It was when I was trying to ask my wife "...bring me that 2-box black thing..." that I decided to give it a name. And as EE hobbyist, and as a beginner EE, I can't do much so, I have to exaggerate to myself and try to tell myself how great it is.Now you gave me a great idea.If my wife ask "why do you call it that."My answer will be "well, I made it for you and I want to remind you that my love for you is forever..." She wont buy it, but she will think I am sweet at least for the moment.

author: Chris C
author_rank: Frequent Contributor
timestamp: October 01, 2015, 06:07:22 pm
content: Quote from: Rick Law on October 01, 2015, 05:40:53 pmHeh, the name is good, with a great backstory.I've been bouncing around the idea of putting 4x Headway 38120S (LiFePO4, 10AH) into series, as kind of a universal battery pack. With a few plug-in boost/buck adapters it could run all of my cordless tools, including my lawn tools, with longer runtime than any of the original packs; maybe I could wear it in a fanny pack or something for portability. When not used, it could prop up the meager capacity of my UPS. During a long blackout, it could be used to charge other battery packs. And so on. Might save me some money in the long run by not having to maintain a myriad of single-purpose battery packs (more than one for some tools with low pack capacity), buying fast chargers, etc. Or at least break even.Whatever the case, I hope Joaquin doesn't put anybody in a position where emergency measures are necessary.

author: Smokey
author_rank: Super Contributor
timestamp: October 03, 2015, 02:15:33 am
content: Quote from: Rick Law on October 01, 2015, 04:58:52 pmAre you joking? Do you take the spare tire and jack out of your car because you haven't gotten a flat in a few years?And about the not being able to get gas in an emergency..... This is why you accept you live in a place that gets natural disasters and you PREPARE for the disaster. Storms give you plenty of time to prepare and stock up on things like fuel and water and food. Not being able to prepare for a disaster in the middle of the disaster is not a good excuse.

author: Rick Law
author_rank: Super Contributor
timestamp: October 03, 2015, 02:30:36 am
content: Quote from: Smokey on October 03, 2015, 02:15:33 amI am not joking. Judging cost v benefit is something I demand of myself.For the same reason, these daysone in 7 cars doesn't have a spare tire, and those with spare tires are "donut tires" instead of "full service tires". Cost v benefit."Why Doesn't My Car Have a Spare Tire?"http://www.angieslist.com/articles/why-doesnt-my-car-have-spare-tire.htm"Your next car may not have a spare tire"http://www.consumerreports.org/cro/news/2014/08/your-next-car-may-not-have-a-spare-tire/index.htm"The spare tire goes missing" (spare tire gone optional)http://www.autonews.com/article/20150203/BLOG06/302039996/the-spare-tire-goes-missingEdit: reworded. Original reply wording was unintentionally combative. Must be too sleepy.

author: djQUAN
author_rank: Frequent Contributor
timestamp: October 03, 2015, 03:04:06 am
content: Quote from: Chris C on October 01, 2015, 06:07:22 pmThose headway cells work nice. I have a 4x 15Ah pack that I used to use for my bike HID headlight (first pic) but now mainly used for my converted old cordless drill. I also have the 6x pack that I mounted in a pelican knockoff to make a waterproof emergency power source.Both packs have DIY individual cell balancing and low voltage cutoff.

author: EEVblog
author_rank: Unknown
timestamp: October 03, 2015, 03:09:10 am
content: Headlamps are the most versatile, as you can always take the light to anything you want to do. And most good ones are regulated and provide 100+ hours from a set of AAA's on the low setting.I can remember we were at dinner on holiday once and the power went off. I had my backpack with our headlamps and loaned them to the chefs and they kept on "cook'n'with gas"!

author: EEVblog
author_rank: Unknown
timestamp: October 03, 2015, 03:12:31 am
content: Quote from: sarepairman2 on October 01, 2015, 02:48:30 amDid you do that by powering stuff direct from the generator with extension leads, or did you plug the output of the generator into a power point, disconnect from the grid and power everything on the existing circuits?As an aside I find it annoying that I have a 3kW solar system that I would become useless if the power went off, even during the day when it's generating.I always wondered if it would be possible to disconnect from the grid, plug a small UPS inverter into a power point so the solar inverter could detect there is power there and switch on?

author: djQUAN
author_rank: Frequent Contributor
timestamp: October 03, 2015, 03:14:36 am
content: Which reminds me, I also have a headlamp that I bought cheap. It used 3x AAAs but it was not convenient (and costlier than using AAs) so I modded it to take cellphone batts.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 03, 2015, 04:42:22 am
content: Quote from: EEVblog on October 03, 2015, 03:12:31 amPull the cover off the junction box and clip some wires to the solar input.

author: bills
author_rank: Frequent Contributor
timestamp: October 03, 2015, 05:02:26 am
content: Quote from: EEVblog on October 03, 2015, 03:12:31 amI have been wondering the same thing, will the inverter sync. with the square wave on the small inverter?Or will this take out some thing in my 3kw. inverter, Will the 3kw try to feed excess current back into the small inverter?

author: djQUAN
author_rank: Frequent Contributor
timestamp: October 03, 2015, 05:07:49 am
content: Quote from: NiHaoMike on October 03, 2015, 04:42:22 amNot sure how his system is configured but the last 3kW grid tied system I built ran with all ten 300W PVs in series totaling 420VDC open circuit, 380V at maximum power. Not sure how you can make use of that

author: bills
author_rank: Frequent Contributor
timestamp: October 03, 2015, 05:13:10 am
content: I guess I will have to find the data sheet on my inverter and check.I also have a 4.5 kw gen set that I have wired in but always disconnect the inverter before testing not brave enough try that with the solar system engaged.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 03, 2015, 05:15:25 am
content: Quote from: djQUAN on October 03, 2015, 05:07:49 amThat sort of voltage will work nicely with a common switching power supply.

author: djQUAN
author_rank: Frequent Contributor
timestamp: October 03, 2015, 05:21:26 am
content: The grid tied inverters from what I understand are current output relying on the grid to sink all the excess current so that the output voltage is regulated. Not sure how it would react to a small inverter that cannot sink all the generated power.Besides, these grid tied inverters have protection such that if the mains frequency varies by a small amount, it will not turn on. Look in your inverter manual for the specific tolerance of mains frequency.

author: bills
author_rank: Frequent Contributor
timestamp: October 03, 2015, 05:23:15 am
content: Quote from: NiHaoMike on October 03, 2015, 05:15:25 amAnd what would you do with that? Short of designing a new system.

author: bills
author_rank: Frequent Contributor
timestamp: October 03, 2015, 05:33:45 am
content: Here is the data sheet for a sunpower inverter.It is close to the one I have but not exact.not much info there I will find the manual for mine tomorrow.http://solarforward.com/wp-content/themes/solarforward/pdf/products/SPR-3000p3600p4200p5000p6000p.pdf

author: sarepairman2
author_rank: Frequent Contributor
timestamp: October 03, 2015, 06:34:44 pm
content: Quote from: EEVblog on October 03, 2015, 03:12:31 amI turn off the circuit breaker that goes to the out side power pole and plug a generator into a feeder. Star power plane.I keep ~10 gallons of guzzoline around that I pour into the car to recycle.I seriously think we only spent like 300$ on the home depot generator, it typically powers 2 refrigerators, lights and a computer. I ran my room AC on it a few times lol..The generator has a 110/220 output, I do need to switch to 220 to pump water from the well though, meaning momentary power interruptions.The only bad thing about it is that my UPS does not like the generator. I think I would need some kind of big ass low pass filter on the output of the generator..I also have a propane room heater and a kerosene heater if shit really hits the fan.We use electric power for cooking... the little cheap generator is not good enough to heat the stove so I just cook on the BBQ during power outages. Typically have 80lbs of propane in stock in little tanks.I do run mine once a month for a few minutes with a ~500 watt heat load, change the oil on it too. I think I had to repair it once or twice because we left it over the winter with gasoline in its tank, but its a champion compared to the fucking lawn mowerIt is a bit of room, but I was feeling great during hurricane sandy when I was one of the few people on my block that had power and cooking that week.