Thinking about a starter system, but no south facing roof

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  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    westbranch wrote: »
    re warranty: there has been such an upheaval in the PV industry, a lot of the best companies have gone out of existence, that placing much value on a warranty is probably an over expectation. just saying...

    Yes, very fair to say. Unless the warranty is backed by some other company.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    techntrek wrote: »
    There are many examples of less-than-apocalypse emergencies taking down the NG system. For your usual outage, no problem. But, for one example, look at the San Francisco earthquake where many NG lines ruptured. A smallish earthquake in the New Madrid fault would cut major lines.

    Yeah, true. In Dallas we have a lot less of a chance of that (though some parts have been having a lot of 1-3 or even 4 scale quakes lately due to all of the shale drilling here!). A generator that could run on gasoline and LP/NG both would be ideal.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    techntrek wrote: »
    I wasn't saying you should follow the same route, only demonstrating that applying insulation somewhere other than in additional glass paid off.

    Haha, yes, I know and understand your point. Still amazing that it was even possible to do this. Great that you could!
  • SolInvictus
    SolInvictus Solar Expert Posts: 138
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    $.99/watt (rated) is good, but is there any problem with the Renogy that I have listed previously at $.92/watt? 25 performance year warranty, 10 year materials.
    I do not know about the quality of the Chinese Renogy panels because my experience is with Solarex (U.S.) and Kyocera (Japanese). Chinese PV panels are the lest expensive. $.70 per watt is around the best retail price for A grade PV, but you probably have to pay shipping, so the Renogy panels are close.

    Renogy is headquartered in the U.S. but manufacturing is in Wuxi, China (Solar States goes to China to partner with Renogy!, September 13, 2011). Their domain is registered to the president of Renogy, Yi Li. Their online press releases start in 2011, and the company may have been founded in 2010 making it almost a 4 year old.

    The Better Business Bureau, Baton Rouge, LA: Renogy, LLC. Overview does not list any complaints.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof

    So I've got my measurements from my Kill-A-Watt to share. For backup use, I'm estimating 10 hours of internet connectivity and laptop use.

    CCTV DVR & 4 cameras = 29W * 24hrs = 696WH/day
    FiOS Modem = 19W * 10hrs = 190WH/day
    FiOS Router = 13W * 10hrs = 130WH/day
    13W CFL Lamp = 11W * 6hrs = 66WH/day
    iPhone charging = 5W * 2hrs = 10WH/day (x's 2 phones = 20W/day)
    iPad charging = 10W * 3hrs = 30WH/day
    IBM X201 work laptop = 45W * 10hrs = 450WH/day
    Aquarium minimum pump = 19W * 24hrs = 456WH/day

    So the minimum we would need to operate these devices each day is 2038WH, and a 200watt inverter (176W actual max use by these devices, but leaving 12% overage).

    For the sake of our calculations, I'm going to ignore the fact that I have a bunch of other UPS systems (total of 120AH worth - 3 APC XS1500, 2 XS battery addons for XS1500's, 1 ES725 and 1 SC600) sitting around already hooked up to the FiOS modem, router, CCTV system and aquarium pump. The FiOS modem has it's own 7.2AH battery as well, so really a total of 127AH. I am going to assume that I've already exhausted those backups or for some reason they failed. The solar system could at least recharge itself eventually, those batteries cannot so they shouldn't be relied upon beyond a few hours of a normal, more common blackout.

    If I take Bill's calculations into account from his previous post, then I come up with this storage requirement:

    2038WH/day * 1/12 volt battery bank * 1/.85 inverter efficiency * 2 days no sun storage * 1/0.50 max battery discharge = 799.21AH 12 volt battery bank.

    This is more than double what we were thinking before, and would require eight 105AH Exide batteries at $108.24 each, or $865 total. That's a bit more battery capacity than I was thinking, but it is what it is. If I took out the CCTV system, then it would be 1324WH or 525AH storage required (5 batteries @ $541), which is more acceptable from a cost perspective. 3 extra batteries required to run a 29W system for 2 days is pretty amazing. I wouldn't have expected that. I do plan on replacing the CCTV system soon with high quality cameras, so I will keep the power requirements of the new system in mind for sure.

    All of this does make the case for a generator as our backup a more realistic and cost effective option though (despite that it burns fossil fuels, has more moving parts to break, makes noise, etc). For the price of just the batteries I can get the whole solution that way. Regardless, I still want to setup something with solar for the fun of it (if nothing else). As long as I stay within reason on expenses and learn along the way, it will be a success. I may go ahead and get a small generator as well.

    On to the solar requirements to charge up 800AH (or 525AH) of batteries:

    800AH * 14.5v charging * 1/0.85 panel + charge controller derating (increased from .77 to .85 since I plan to get an MPPT CC) * 0.05 charge rate = 682W array (448W if 525AH battery capacity). 5% charge rate should be fine for this system since it would not be used daily.

    Sun requirements (I think... what else would you call this calculation of watts?):

    2038WH/day * 1/0.52 system efficiency * 1/5 hours of sun = 783.8W array (or 533.7W array without the CCTV). Right about 5 hours of sun for Dallas report by the solar insolation map I found instead of 4.

    So, putting all of this together, on the higher end I would probably be looking at a 1kWH system (oversize now for a bit of future growth) consisting of four 250watt panels for $1160 (found out shipping was not included before), MorningStar TriStar 45amp MPPT CC ~ $450, eight 105AH Exide batteries $865, and random 300-400W pure sine wave inverter ~$125. Wire and other supplies ~$250. Total around $2850, but better round it up to $3k.

    The lower end system I'd probably go with a 600WH system (still oversizing a bit) consisting of two 300watt panels for $752 shipped, Tracer 40A MPPT CC $220, five 105AH Exide batteries $541, random 300-400W pure sine wave inverter ~$125. Wire and other supplies ~$250. Total around $1880, but round up again to $2000.

    This all seem reasonable?

    One other question is how much would I expect to pay someone just to do the install of the rails and panels on my roof? That's one part I would definitely consider paying someone else to do. I do all my own engine work, house remodeling, plumbing, etc... but as I've mentioned before, hanging out on the roof is not my favorite thing to do. After seeing the full install of that system in Plano, TX that is a sticky, I certainly will double check reviews/references of anyone that I would pay to do this!

    Lastly, if I don't use the system that often, it seems logical that the power not being used to trickle charge the batteries should be put to use on the house grid. I guess this would make it a hybrid system (or grid-tie with batteries?)? What would it take to to do this? Just an additional inverter that is hooked into the main panel? From what I've seen on the grid-tie systems, I could see this requiring a sub-panel with cut-off switch and other things as well.

    Thanks again for all of your assistance. This is really a great help. I'll keep searching through some of the other threads on here for some of these answers as well.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    I do not know about the quality of the Chinese Renogy panels because my experience is with Solarex (U.S.) and Kyocera (Japanese). Chinese PV panels are the lest expensive. $.70 per watt is around the best retail price for A grade PV, but you probably have to pay shipping, so the Renogy panels are close.

    Renogy is headquartered in the U.S. but manufacturing is in Wuxi, China (Solar States goes to China to partner with Renogy!, September 13, 2011). Their domain is registered to the president of Renogy, Yi Li. Their online press releases start in 2011, and the company may have been founded in 2010 making it almost a 4 year old.

    The Better Business Bureau, Baton Rouge, LA: Renogy, LLC. Overview does not list any complaints.


    Thanks for helping out on the research for this. I emailed Renogy earlier since I noticed that their pricing on Amazon Prime was quite different than the pricing on their website. I did a sample purchase and went to check out but shipping/tax never showed up. They finally responded back that it would be a flat $200 to ship 4 250W panels to a location I would pick up from somewhere around DFW. Quite a bit. So yes, you're definitely correct about adding shipping making them closer to the price of others.

    The reviews on amazon are great for Renogy, so I don't think there would be any issue ordering from them, but I will certainly take a closer look at Solarex and Kyocera.

    Thank you.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    If I take Bill's calculations into account from his previous post, then I come up with this storage requirement:

    2038WH/day * 1/12 volt battery bank * 1/.85 inverter efficiency * 2 days no sun storage * 1/0.50 max battery discharge = 799.21AH 12 volt battery bank.

    For different reasons, the 0.77 derating works for both PWM and MPPT--The 0.85 is (in my humble opinion) is a bit on the optimistic side.

    Second, that is a pretty large AH battery bank. Roughly 4 parallel strings of "golf cart" batteries or 8 parallel 12 volt 105 AH batteries.

    Several suggestions--First I recommend 1 parallel string as "optimum" and 2-3 as a typical maximum of parallel batteries. It can be difficult guarantee current sharing, lots of connections (each one should string should have its own fuse/breaker for safety). Also, if you have flooded cell batteries, you have to check a bunch of cells for watering.

    Another issue is an 800 AH battery bank... At 10% rate of charge, that is ~80 amps of charging current--About the maximum a single high end MPPT controller can output--Any higher charging current, and you need a second charge controller.

    If you go to 24 volts, the wiring/current is 1/2--and 1/2 the parallel strings. However, you need a 24 volt AC inverter--And it can be difficult to find a "smaller" 24 VDC input inverter.

    Lots of "paper designs" and tradeoffs.
    This is more than double what we were thinking before, and would require eight 105AH Exide batteries at $108.24 each, or $865 total. That's a bit more battery capacity than I was thinking, but it is what it is. If I took out the CCTV system, then it would be 1324WH or 525AH storage required (5 batteries @ $541), which is more acceptable from a cost perspective. 3 extra batteries required to run a 29W system for 2 days is pretty amazing. I wouldn't have expected that. I do plan on replacing the CCTV system soon with high quality cameras, so I will keep the power requirements of the new system in mind for sure.

    Yep--24 hour loads are real "killers". Conservation or just not using security cameras but using "trail cameras" (motion sensing, write to memory card) with a few AA batteries--I.e., change the requirements to reduce loads.

    And fixed loads that are a bit of a pain. Solar is a variable power source--Sometimes you get more, sometimes less... If you need to power "fixed" loads during periods of poor sun, then you need more panels or backup genset. If your loads are optional--You just turn them off until the sun returns.
    All of this does make the case for a generator as our backup a more realistic and cost effective option though (despite that it burns fossil fuels, has more moving parts to break, makes noise, etc). For the price of just the batteries I can get the whole solution that way. Regardless, I still want to setup something with solar for the fun of it (if nothing else). As long as I stay within reason on expenses and learn along the way, it will be a success. I may go ahead and get a small generator as well.

    And you design the battery/solar system to supply "convenient"/quiet AC power (lights/radio/computer at night/off peak--And run the genset during the day (heavier loads) when somebody is available to start/monitor the genset (and noise is not a problem).
    Sun requirements (I think... what else would you call this calculation of watts?):

    PV Watts for Fort Worth Texas, fixed array, tilted to latitude:
    Month    Solar Radiation (kWh/m 2/day)
    1      4.32     
    2      4.77     
    3      5.50     
    4      5.98     
    5      6.02     
    6      6.25     
    7      6.39     
    8      6.31     
    9      5.83     
    10      5.56     
    11      4.43     
    12      4.10     
    Year      5.46
    

    You pick your "break even month" -- I suggest tossing the bottom three months (assume generator) and the 4th lowest month is "break even" (may or may not use genset depending on weather). You could also pick 4 hours or even ~3.5 hours if you want some headroom for bad weather (some places have less than 2-3 hours during poor weather/winter months and having a backup genset is pretty much a necessity).
    2038WH/day * 1/0.52 system efficiency * 1/5 hours of sun = 783.8W array (or 533.7W array without the CCTV). Right about 5 hours of sun for Dallas report by the solar insolation map I found instead of 4.

    No correct answers, just what works for your needs/wallet.
    So, putting all of this together, on the higher end I would probably be looking at a 1kWH system (oversize now for a bit of future growth) consisting of four 250watt panels for $1160 (found out shipping was not included before), MorningStar TriStar 45amp MPPT CC ~ $450, eight 105AH Exide batteries $865, and random 300-400W pure sine wave inverter ~$125. Wire and other supplies ~$250. Total around $2850, but better round it up to $3k.

    The lower end system I'd probably go with a 600WH system (still oversizing a bit) consisting of two 300watt panels for $752 shipped, Tracer 40A MPPT CC $220, five 105AH Exide batteries $541, random 300-400W pure sine wave inverter ~$125. Wire and other supplies ~$250. Total around $1880, but round up again to $2000.

    This all seem reasonable?

    Pick different batteries (higher AH capacity, less parallel connections). Use 0.77 for charge controller+panel deratings. Think again if 5 hours is your "hours of sun" choice or something less.
    One other question is how much would I expect to pay someone just to do the install of the rails and panels on my roof? That's one part I would definitely consider paying someone else to do. I do all my own engine work, house remodeling, plumbing, etc... but as I've mentioned before, hanging out on the roof is not my favorite thing to do. After seeing the full install of that system in Plano, TX that is a sticky, I certainly will double check reviews/references of anyone that I would pay to do this!

    Use a roofer to install the rails... My roofer thought about getting into GT solar because he spent so much time fixing leaky roofs after the electrical contractor installed the array (poor flashing, breaking tile, etc.).
    Lastly, if I don't use the system that often, it seems logical that the power not being used to trickle charge the batteries should be put to use on the house grid. I guess this would make it a hybrid system (or grid-tie with batteries?)? What would it take to to do this? Just an additional inverter that is hooked into the main panel? From what I've seen on the grid-tie systems, I could see this requiring a sub-panel with cut-off switch and other things as well.

    Hybrid systems tend to be larger (4+ kW rated inverters). There are smaller (~400 Watt) hybrid inverters (or battery/solar/wind based plug and play GT Inverters)--But they (so far) have not been UL/NRTL approved and are technically illegal to install (and the unlisted devices seem to also be unreliable).

    In many places, building permits are expensive and sometimes GT Solar fixed meter charges/etc. are not cheap. Smaller GT systems may not be worth the money to do the install (fees, permits).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    What kind of pricing should I expect for 6V ~200AH batteries? ...

    I am not in the solar business... So, I don't really keep up on prices. And we really do not want to turn the forum into "...here is the cheapest place to get xyz".

    Our host NAWS does sell solar products and lists their prices online--From what I understand, they have pretty good prices so that can be your bench mark.

    Batteries brands are, many times, made to order (for Walmart, Costco, etc.). And the actual company building the battery can change over time. If you find a good deal and want to ask folks here their experiences with that brand/model--Feel free.
    Yes, I'm a big nerd when it comes to tying things in to monitor on a computer, however if the cost is 3-5x's that to get devices that can monitor, I can live without. I do not have a well pump. We're in DFW so we have city water. If the power to the water tower goes out, I have 200 gallons of RODI waste water that we store if there ever is a real emergency for a long period of time (and a lifestraw to drink out of it since it's not 100% contaminate free). If it comes to this, we have serious problems :).

    There are some folks here building monitor and control systems with Arduino processor boards... Perhaps you can get some information/ideas there. Searching with Google and the "site:" tag makes finding things easier on the forum sometimes:

    arduino site:wind-sun.com

    There can be really weird things to worry about with regional power failures--One poster here had the sewer main backup into his home. He dug up the lateral and installed a septic field valve (and there are check/diversion valves for laterals too). When the city loses power, water, sewer pumping, garbage trucks, etc. go away... Staying in a home for weeks into a region emergency may not be practical.
    1-2 gallons a day is not bad. natural gas would certainly be ideal. Better for environment and unlimited supply (again as long as service is on - and if it's not, we have big problems again).

    I should add that I plan on using ~400 watts of power to "run my home" (lights, refrigerator, cell charger, etc.). The Honda will run 9+ hours on 1 gallon of fuel at 400 watts. At full power (1,600 watts), it will still run ~4 hours per gallon. Small loads and small gensets are much easier to store fuel for (I keep ~20 gallons + fuel stabilizer that I recycle in the vehicles once a year). The extra fuel and portable genset lets me decide if I shelter in place or bug out. A large solar power system is not exactly portable.

    Regarding natural gas, I have lived just south of San Francisco for almost 60 years. We have never lost natural gas yet--However, I chose to use gasoline for backup fuel (probably should think about a natural gas genset--but past 10-14 days of shelter in place--either things are going to be better, or get worse).

    Earthquakes in California are actually very localized effects. The energy dissapates over distance fairly quickly, and the actual damage is dependent on geology and reflections of seismic waves. In the quakes so far, you can go just a few blocks to a couple of miles to a pretty much unaffected area.

    However, in the midwest and east coast, the older basalt rocks (California has "newer" "plastic" rocks) will ring like a bell and can affect multiple states with strong seismic waves. Plus California tends to have better earthquake codes and newer construction (non brick/masonry construction) than many older towns. Not sure what a New Madrid quake would look like--But probably not pretty.
    I'm going to see if I can get on the roof on New Year's day when it should be 60+ deg here and measure the area that faces south to see what I've got to work with there. The west facing area would certainly be able to hold 4-6 200-300watt panels if I wanted to, and I'm guessing the south is only 4 max. The 250-300watt panels I see are mostly 24V, so it seems that this would be adequate for the DC wire run to the garage (which would be around 80ft estimated) since you said a higher voltage array would be best. Correct?

    Not that high voltage is "best", but it can make longer wire runs for higher powered solar arrays much easier. Downside is that MPPT charge controllers are not cheap.
    This website has a good calculator for figuring voltage drop, and only 2.1-3.4% seems reasonable for 80ft 8/10awg copper (respectively) on 150VDC 32A (if I had four 300W panels running 37Vmp & 8Imp per panel). If I only had half these panels (two 300W) then it would be 4.3-6.8% loss. As you said, the higher the voltage, the less drop, so running higher voltage makes sense to me.

    The typical high end MPPT controller will work with a Vmp-array of ~100 VDC maximum (cold temperatures means higher Voc in winter--You need to use the sizing tool for the MPPT charge controller to size/configure the array for the specific controller). There are higher input voltage charge controllers, but they tend to cost more and have a lower output current rating.

    Again, multiple paper designs to see what works best for you. No "simple/quick" answers when doing your own engineering.
    That's pretty nice - even my 32" LCD gets kinda warm. It's pretty old now though. Not LED LCD.

    I should add, the TV is an LED LCD unit (much more efficient)... The prior 32" LCD TV with CFL's ran about 150 watts and did a pretty good job of taking the chill off our bedroom.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    So I've got my measurements from my Kill-A-Watt to share.
    <snip>
    So the minimum we would need to operate these devices each day is 2038WH, and a 200watt inverter (176W actual max use by these devices, but leaving 12% overage).

    Many of your loads have very poor power factor. You should plan on at least a 300 watt inverter.
    glocklt4 wrote: »
    For the sake of our calculations, I'm going to ignore the fact that I have a bunch of other UPS systems (total of 120AH worth - 3 APC XS1500, 2 XS battery addons for XS1500's, 1 ES725 and 1 SC600) sitting around already hooked up to the FiOS modem, router, CCTV system and aquarium pump.

    If these UPSs are powered by the output of your inverter you CANNOT ignore the load they present. If they are powered directly from the grid, you will need transfer switches to switch over from the UPS to the inverter.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    vtmaps wrote: »
    Many of your loads have very poor power factor. You should plan on at least a 300 watt inverter.

    If these UPSs are powered by the output of your inverter you CANNOT ignore the load they present. If they are powered directly from the grid, you will need transfer switches to switch over from the UPS to the inverter.

    --vtMaps

    Thanks for the info. I noticed the VA on my Kill-A-Watt was quite a bit higher than the W. Power factor is something I wasn't familiar with before but am reading on.

    The UPSs are powered by the grid and I would just manually plug them into whatever backup solution I use when needed. Not going to setup a transfer switch to house main panel.

    EDIT: After re-reading what you said, I think you were talking about transferring the device plugged into the UPS into the solar inverter. I'm ok with directly plugging in any necessary devices to another power source manually.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    BB. wrote: »
    For different reasons, the 0.77 derating works for both PWM and MPPT--The 0.85 is (in my humble opinion) is a bit on the optimistic side.

    Got it, thanks.
    BB. wrote: »

    Second, that is a pretty large AH battery bank. Roughly 4 parallel strings of "golf cart" batteries or 8 parallel 12 volt 105 AH batteries.

    Several suggestions--First I recommend 1 parallel string as "optimum" and 2-3 as a typical maximum of parallel batteries. It can be difficult guarantee current sharing, lots of connections (each one should string should have its own fuse/breaker for safety). Also, if you have flooded cell batteries, you have to check a bunch of cells for watering.

    Another issue is an 800 AH battery bank... At 10% rate of charge, that is ~80 amps of charging current--About the maximum a single high end MPPT controller can output--Any higher charging current, and you need a second charge controller.

    If you go to 24 volts, the wiring/current is 1/2--and 1/2 the parallel strings. However, you need a 24 volt AC inverter--And it can be difficult to find a "smaller" 24 VDC input inverter.

    Lots of "paper designs" and tradeoffs.

    yeah, I agree with you that 800AH seems like quite a bit. 24V would be the way to go to cut the amps in half and stay within range of most of the MPPT controllers.

    BB. wrote: »
    Yep--24 hour loads are real "killers". Conservation or just not using security cameras but using "trail cameras" (motion sensing, write to memory card) with a few AA batteries--I.e., change the requirements to reduce loads.

    And fixed loads that are a bit of a pain. Solar is a variable power source--Sometimes you get more, sometimes less... If you need to power "fixed" loads during periods of poor sun, then you need more panels or backup genset. If your loads are optional--You just turn them off until the sun returns.

    And you design the battery/solar system to supply "convenient"/quiet AC power (lights/radio/computer at night/off peak--And run the genset during the day (heavier loads) when somebody is available to start/monitor the genset (and noise is not a problem).

    Yeah, agree about the 24 hour loads and gen set during the day. In an effort to make all of this more reasonable and overall much more cost effective, I ordered a 3000W CPE generator last night that was on slickdeals for only $179+ tax (amazing...). For emergency use this will be fine. Even if I still plan out a decent solar system, that's cheap enough to justify a 2nd backup on another fuel source in general. I know it's not an inverter type, so it's bulkier and will burn more fuel, but it's advertised as 3.8gal (full capacity) burn in 12 hours at 50% usage - 1500W. I can get a 5gal storage tank for another ~15 hours (and even have a hand pump at home already to extract fuel from the cars if we had to go to that extreme). I can keep this generator under my deck out back (with cover of course) and even use it from there with extension cords to power the critical systems during the day (not that far of a run). I could probably charge up my UPSs during the day on this as well and then run the majority of the devices I mentioned on those UPSs at night if the generator is too loud (though it's advertised at 68db, which is not bad). I would hope that 2700W (3000W capacity - 300W or so in my listed appliances) would be enough to charge up the UPSs, but i will have to confirm with the Kill-A-Watt. I can't remember the last time that I've run the UPSs down all the way to see how long they take the fully charge back up either, so it could end up being 12+ hrs before they are close to full (on the larger AH ones). I'll schedule a test and see.
    BB. wrote: »

    PV Watts for Fort Worth Texas, fixed array, tilted to latitude:
    Month    Solar Radiation (kWh/m 2/day)
    1      4.32     
    2      4.77     
    3      5.50     
    4      5.98     
    5      6.02     
    6      6.25     
    7      6.39     
    8      6.31     
    9      5.83     
    10      5.56     
    11      4.43     
    12      4.10     
    Year      5.46
    

    You pick your "break even month" -- I suggest tossing the bottom three months (assume generator) and the 4th lowest month is "break even" (may or may not use genset depending on weather). You could also pick 4 hours or even ~3.5 hours if you want some headroom for bad weather (some places have less than 2-3 hours during poor weather/winter months and having a backup genset is pretty much a necessity).

    No correct answers, just what works for your needs/wallet.

    Pick different batteries (higher AH capacity, less parallel connections). Use 0.77 for charge controller+panel deratings. Think again if 5 hours is your "hours of sun" choice or something less.

    I do think that 5hrs sun rating would be acceptable here based on that info. Also, now that I have the generator on order, that would make up for when there is bad weather and in winter (as you mentioned), so I can knock those outliers off that way.

    BB. wrote: »
    Use a roofer to install the rails... My roofer thought about getting into GT solar because he spent so much time fixing leaky roofs after the electrical controller installed the array (poor flashing, breaking tile, etc.).

    Great point, thanks. Makes the most sense. Then hopefully I could spend minimal time putting the panels up if I wanted to do that myself still.
    BB. wrote: »
    Hybrid systems tend to be larger (4+ kW rated inverters). There are smaller (~400 Watt) hybrid inverters (or battery/solar/wind based plug and play GT Inverters)--But they (so far) have not been UL/NRTL approved and are technically illegal to install (and the unlisted devices seem to also be unreliable).

    In many places, building permits are expensive and sometimes GT Solar fixed meter charges/etc. are not cheap. Smaller GT systems may not be worth the money to do the install (fees, permits).

    Ok, yes, I think those systems are too big for my application/budget. I'll stay away from hybrid.



    So now that I have the generator ordered as a high power emergency source for my heavier loads (and hopefully recharging UPSs to use with low power appliances when generator is off), I can relax the requirements of my solar system considerably, especially the battery capacity. I definitely do not intend to spend the money for a grid-tie system when we've all discussed that I can do far more to reduce my energy bills by conservation, so my $ is much better spent there first if that was my approach. I mentioned before that I'd like to do a solar system of some kind even if it's just for learning how it all works. Perhaps even a single panel, low amp PWM charger, single battery storage and small inverter would be fine then. I could see one that size being used just for cell phone or laptop battery charging (in a disaster if generator is dead of out of fuel and we need communication), or maybe a rain barrel pump I've been thinking about adding to my rain barrel system which would only run for 10mins every day or two usually. I could also use that to keep my boat batteries topped off over the winter (with a 12V system at least).
  • jcheil
    jcheil Solar Expert Posts: 722 ✭✭✭
    Re: Thinking about a starter system, but no south facing roof

    Also be aware that at night, your DVR cameras will draw more power since the IR LEDS will be turned on. My 16 cameras and DVR draw 58w daytime and 90w nighttime. YMMV
    Off-Grid in Central Florida since 2005, Full-Time since June 2014 | 12 X Sovello 205w panels, 9 X ToPoint 220w panels, 36x ToPoint 225w panels (12,525 watts total) | Custom built single-axis ground mounts | Complete FP2 Outback System: 3 x FM80, 2 x VFX3648, X240 Transformer, FLEXnet-DC, Mate-3, Hub-10, FW500 AC/DC | 24 x Trojan L16RE-B Batteries 1110ah @ 48v | Honda EU7000is Generator and a pile of "other" Generators | Home-Made PVC solar hot water collector | Custom data logging software http://www.somewhatcrookedcamp.com/monitormate.html
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    jcheil wrote: »
    Also be aware that at night, your DVR cameras will draw more power since the IR LEDS will be turned on. My 16 cameras and DVR draw 58w daytime and 90w nighttime. YMMV

    Great point. I did not measure them at night with the IR LEDs on. I will definitely check that out.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Thinking about a starter system, but no south facing roof

    "...if the generator is too loud (though it's advertised at 68db, which is not bad). "

    It is going to be much louder than you think. My 12 kw Generac is rated at 70.5 dba @ 23 feet at full load, which I consider to be loud even with no load.

    I would also consider a 2 kw Honda or Yamaha inverter-genset in the future - add it to your long-term budget. Your 3 kw contractor screamer should really only be used for bigger loads as-needed due to its fuel consumption. If you are running a genset all day long you WILL want the inverter-genset to save fuel. For comparison I have a 2400 watt Yamaha and with about 1000 watt average load it will run for 8 hours on 1.5 gallons of gas. Since you are creating your system to handle long-term outages under conditions where getting gasoline may not be possible, every gallon of gas you save means another X number of hours you still have electricity after a week or two.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    techntrek wrote: »
    "...if the generator is too loud (though it's advertised at 68db, which is not bad). "

    It is going to be much louder than you think. My 12 kw Generac is rated at 70.5 dba @ 23 feet at full load, which I consider to be loud even with no load.

    I would also consider a 2 kw Honda or Yamaha inverter-genset in the future - add it to your long-term budget. Your 3 kw contractor screamer should really only be used for bigger loads as-needed due to its fuel consumption. If you are running a genset all day long you WILL want the inverter-genset to save fuel. For comparison I have a 2400 watt Yamaha and with about 1000 watt average load it will run for 8 hours on 1.5 gallons of gas. Since you are creating your system to handle long-term outages under conditions where getting gasoline may not be possible, every gallon of gas you save means another X number of hours you still have electricity after a week or two.

    Yep, understand what you're saying about fuel consumption. I'll give this one a try and if it doesn't work well for me in testing I can always give it to my sister or parents for them to use as backup and get an inverter generator. They are easily 4-10x's the price though. This one was just too cheap to pass up. I love Honda as they make some of the most reliable mechanics on the planet (for consumers), so yes, that would be my long-term goal. Noise is not really as big of an issue as I was making it out to be before since we do not have any houses behind us (ponds and golf course go on for a while), and if weather is good enough that it can run under our deck outside (which is on a good grade slope), I bet we don't hear anything at all in the house and neither would neighbors in their houses. If we have to run it closer to the house, I'd certainly be ok with the noise during the day over having no power. My direct neighbors are cool though, and if anything they would be asking for some power off of it too.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof

    Well my order of the 3kw generator got cancelled, haha. So it was too good of a deal to be true. Guess I get some more time to research inverter generators now to see if I can find a good deal on one after all. As far as solar goes, I'm may see about getting on the roof today to measure how much actual south facing sqft we have and will go from there with a kit. I'm guessing a 400-500W system may be possible still. We'll see.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof

    After thinking about it and doing research on other generators now that the deal on that 3kW one is dead, I think I've decided to go with a Yamaha 1kW inverter generator and then a 400-500W solar system to pair with it. This would give me redundancy in the form of multiple "fuel" types, and combined should be able to power just about anything we need to with the power out. The generator can run until fuel is out, and theoretically the solar system would keep basics running as sun availability is there. Like Bill said though, at some point you just abandon the house if you go too long without power. I don't plan to tie the generator to the house grid, and solar wouldn't be tied either (for now at least). Still going to plan on solar use for some backup (with 300-400AH in batteries) but also for running LED Xmas lights, rain barrel pump every couple days when it's not winter, and some other random things.

    I tried to get on the roof this afternoon to measure the south facing part of our roof, but I ended up coming right back down once I was up there for a few mins. Even with very good tennis shoes on that usually provide a lot of traction, our composition roofing was just too slick for the slope. I didn't feel comfortable up there at all. If it was a bit flatter, it would have been no problem, but I saw myself sliding off way too easily. 20+ft drops off our 2nd story are not my way of starting the new year!

    So, going to call a couple solar companies around town and then also a couple roofing companies to try and get a quote for labor of installing panels for me. I did spend a lot of time looking at the south facing part of the roof from the ground though, and I really don't think I could get any more than two 200-300watt panels up there max, and only one in one spot, and another on the other side of a skylight about 5-7 ft away.

    It looks like the west side of the roof is going to be the best spot. If I can put the panels on the west side, I think I've decided that I'm also more open to trying to angle the panels towards the south with mounting brackets. Is there a set of brackets that you guys recommend to do this with? I'll have to see how the optimal tilt would look, but I'd be ok with it still angled to south but not at the perfect spot. Any tilt to the south sounds like it would help lower losses during the winter.

    Also I read a lot into the HPWH (heat pump water heaters) and they sound very neat. When our water heater dies we will definitely go with one of them (though tankless may be an option as well, depending on the amount of electrical work that would have to be done).

    EDIT: I found the Honda EU2000i for not much more than this 1kW Yamaha, so makes sense to get it instead ($714 vs $889 + free shipping, no tax). It's also $100 less than the Yamaha 2kW too, so a good deal. As I have been reading in some other threads, the slightly larger generator could be used to charge solar batteries if weather is bad. Plus the extra 1kW (actual 700kW since original one I mentioned is running of 900W and this is 1600W) would give more options on things we run in the house while it's on anyway. I could keep lights on aquarium going for example (which would be ideal since corals shouldn't go days without "sun). With a 2kW generator, I don't think I would need solar at all, so if roof install cost ends up being more than I want to go with, this additional $170 on the generator will be well spent. At that point a 100W Renogy solar system could be just something to have fun and play with. I could even mount it on some bracket on the side of the house or something.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Thinking about a starter system, but no south facing roof

    On your property, could you put solar panels out as a patio roof/shade?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof

    I read through our HOA covenants and just saw that any "improvements" have to be approved by the HOA. There is a large tree on my neighbor's yard south of my house that would shade panels in many places lower down on the house. The top of our deck arbor would be perfect to completely cover in flat panels if that tree wasn't there. The pond, golf course and neighborhood behind us is a completely different city and HOA, so I was thinking that the back (west) side would be no problem with anything I do. I am not a fan of our HOA and was going to avoid bringing anything up specific to a solar install if it was only a couple of panels. If I was doing a significant install of multi-kW, then I would of course.

    I'll do some more thinking about possible places besides the house roof. If there is a good website resource of mounting hardware (pole, side of house, etc...) that you know of, that may help spark some more ideas for me.

    BTW, I just ordered the EU2000i for $889.99 shipped free. I think I'll be extremely happy with that purchase! (especially when we have a power outage, but I bet I figure out many other ways to use it too).
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    ...Like Bill said though, at some point you just abandon the house if you go too long without power....

    ... I found the Honda EU2000i for not much more than this 1kW Yamaha,....

    I disagree, if you make the right plans so the end of your gasoline supply isn't a problem. A small wood stove (not pellet) in an unused corner, even if you normally never use it, keeps the house anywhere from tolerable to warm even w/o a circulation fan. A solar water system can run its circulation pump from its own PV panel; this saves fuel that would otherwise be powering an electric element water heater or heat pump water heater. Add a 1-2 month supply of dry and canned food, and gallon jugs of water for when the rain barrel is frozen (if you don't have a well, see below), and you can shelter in place just fine short of major damage to your house.

    That Honda is another step in the right direction, since you can keep a good supply of fuel on hand that will last a while. In a big emergency you only have to run it for an hour every couple of hours to keep a fridge and freezer cold, even up to 8 hours, so 20 gallons can last for weeks. During that time you only eat the stuff in your fridge until it is empty, then you start on your dry/canned supply. Obviously you can stop running the genset every few hours so your remaining fuel supply lasts much longer.

    If you have a well, still look into a cheap contractor screamer in the 5-6 kw range. You'll only have to run it for 20 minutes every other day for a shower and to fill up water jugs. It will also be a secondary power source if the Honda has a problem.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Thinking about a starter system, but no south facing roof

    Don't forget to install a proper transfer switch for the hook up to allow safe use of the Honda... It stops the repair lineman from getting fried or worse.
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Thinking about a starter system, but no south facing roof
    westbranch wrote: »
    It stops the repair lineman from getting fried or worse.

    OK, I will rise to the bait.... what's worse than frying a lineman? --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Thinking about a starter system, but no south facing roof

    Does dead do it? I was thinking about a non lethal burn.
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    westbranch wrote: »
    Don't forget to install a proper transfer switch for the hook up to allow safe use of the Honda... It stops the repair lineman from getting fried or worse.

    I don't intend to hook the genny up to the grid (for now), but if we do end up going that route I will certainly use a transfer switch. The EU2000i would only be able to run 1-2 circuits on the house anyway, and the things we will use it for will be easy to hook up via extension cord. Thanks for your comment though. Would not be fun to have grid power off as a line man and then all the sudden get a jolt from opposite side. I'm sure they test the line before handling, but can't prevent someone from turning on a generator while work is in progress.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    techntrek wrote: »
    I disagree, if you make the right plans so the end of your gasoline supply isn't a problem. A small wood stove (not pellet) in an unused corner, even if you normally never use it, keeps the house anywhere from tolerable to warm even w/o a circulation fan. A solar water system can run its circulation pump from its own PV panel; this saves fuel that would otherwise be powering an electric element water heater or heat pump water heater. Add a 1-2 month supply of dry and canned food, and gallon jugs of water for when the rain barrel is frozen (if you don't have a well, see below), and you can shelter in place just fine short of major damage to your house.

    That Honda is another step in the right direction, since you can keep a good supply of fuel on hand that will last a while. In a big emergency you only have to run it for an hour every couple of hours to keep a fridge and freezer cold, even up to 8 hours, so 20 gallons can last for weeks. During that time you only eat the stuff in your fridge until it is empty, then you start on your dry/canned supply. Obviously you can stop running the genset every few hours so your remaining fuel supply lasts much longer.

    If you have a well, still look into a cheap contractor screamer in the 5-6 kw range. You'll only have to run it for 20 minutes every other day for a shower and to fill up water jugs. It will also be a secondary power source if the Honda has a problem.

    I think we are fine as far as heating goes. We always keep a cord of wood out back, and we are in Texas after all. If we can't make it a week without heat then the it's like "The Day After Tomorrow" and we're the new north pole, haha. Agree with you on keeping canned food and jugs of water. I keep 25 gallons of fresh RODI water to use for the aquarium at all times in the garage that won't freeze, but good reminder that the rain barrels could be frozen. I do have 200-250gal usually sitting around though. With the LifeStraw I think we have plenty of options for fresh water to last a while. No wells around our area - just city water.

    Yeah, cannot wait to get the Honda in. As I mentioned earlier, I have a Tahoe that holds 26 gallons and wife's MKZ hybrid holds 12 gallons. Corvette holds 18. The Tahoe and MKZ are always full when bad weather comes around, and I try to keep the Corvette topped off most of the time. That plus a 5-10 gal storage container in garage would keep us running with this generator for a couple months it seems haha.

    A well would certainly be nice, but we're in the "big city" :).
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    I'm sure they test the line before handling, but can't prevent someone from turning on a generator while work is in progress.

    I'm friends with a lineman. The power company here tested a massive clamp-on meter, briefly. It was too dangerous to get the thing in place so they stopped. They just clamp the line to ground while working on it after putting on the big rubber gloves/vest, there is a ground line run up the inside of the bucket's arm that they ground while still on the ground. They still treat the lines as if they were live.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • chief
    chief Registered Users Posts: 3
    Re: Thinking about a starter system, but no south facing roof
    glocklt4 wrote: »
    Thanks, Bill. Great advice all around. The biggest way for us to conserve energy here in Dallas is by turning the temps up during Summer, but convincing the wife to run fans off of a solar system instead of running the A/C at lower temps is a lost cause :). I'm not entirely aiming to save money. Power during a blackout is priceless though when you're a computer nerd like myself. Our longest power outage has only been about a day, and that was due to a microburst (if you're not familiar with storms, it's basically straight line winds that can hit 100mph). It took out major power lines everywhere that took a while for the elec company to get back going. Also a few weeks ago we were very lucky to still have power after the huge ice storms here.

    I live up the street from you and am building an off grid setup very similar to your needs. Besides the severe storms we get here, the "rolling black-outs" we've had recently make me question the future capacity and reliability of the Texas grid. Population around here is growing like crazy with a slow awareness of the need to conserve. The increase of "alternative" energy into the grid is great, but will ultimately decrease reliability.
    I will P.M. you the details of my setup, maybe it will help.
  • glocklt4
    glocklt4 Solar Expert Posts: 29
    Re: Thinking about a starter system, but no south facing roof
    chief wrote: »
    I live up the street from you and am building an off grid setup very similar to your needs. Besides the severe storms we get here, the "rolling black-outs" we've had recently make me question the future capacity and reliability of the Texas grid. Population around here is growing like crazy with a slow awareness of the need to conserve. The increase of "alternative" energy into the grid is great, but will ultimately decrease reliability.
    I will P.M. you the details of my setup, maybe it will help.

    Got it, cheers!