Baja Surf Shack

bajasurfer · July 2008

Hello All,
My friend Dave & I scored a humble shack in Baja last year & we've been making improvements to it ever since. No electricity...so Dave went straight to gas generator, while I believed PV solar was the way to go. I knew zero about solar at the outset, yet dove right in without researching a great deal...and it shows.

Budget constraints also meant 100% piecemeal with low cost parts, plus I had to prove that it would work before we continued to spend; having to convince my buddy to share costs & he stopped participating at 40W. It's my own personal interest in PV solar that appears after the 40W mark.

What follows is the documentation I've kept thus far on the PV solar journey. I share it with you in my 1st post to this forum in hopes that solar-smart people will offer input, making me smarter in the process; to be able to go from rinky-dink setup to a sustainable system. The goal is not a fancy grid-tie system [there's no grid!], just something to make our surf shack more civilized.

Thank you for your time.

Home away from home. It's been repainted to camo-green since this pic.

Part One

Location
Baja California, Mexico [Approx N32º 09' 16", on the coast]
Cottage- 2 bedrooms, 1 full bathroom, full kitchen, living room. [~900 ft²]
Escape house once oil runs dry & anarchy reigns supreme in US.
We'll live off the ocean & home grown vegetables.

Purpose
Reduce dependence on candles, gas lamps, & eliminate using Dave's noisy/smelly/gas guzzling 3500W generator for coffee, TV, PS2, iPod, PCs.

Original System [May 2008]
Designed by someone who figured that trickle chargers were 5W, so 40W should be plenty.
-> 40W total [~2.2 Amps]. One [1] 20W panel* & two [2] 10W panels, all mono-crystalline Suntech cells.
-> Sunforce 60012 7 Amp Charge Controller [14AWG]
-> 2-year old 85AH deep cycle battery. [hybrid, abused in boat & this house]
-> Xantrex 700W inverter** [10AWG]

Mounting Notes
Panels mounted using plywood & L-brackets from Home Depot. Leftover white ceramic tiles were added to the plywood in front of all of the panels- not for more light, but to help reflect heat away from the panels. The balance of the wood was painted a reflective silver. All connections were heat-sealed & wiring was shrouded & taped. Panels are @ [very] slight SW & angle of ~35° from horizontal due to wind concerns, more than output. They have been getting solid 5 hours of intense sunlight per day since mid May, with not many cloudy days.

*

**

Load, 3 to 4 weekends per month
-> Three [3] 12V x 26W 1.4 Amp fluorescent fixtures; living room (2) & kitchen (1) [One broken, needs ballast]
-> Two [2] 12V x 15W 1.3 Amp fluorescent fixtures; bedrooms [One needs new bulb]
-> One [1] 12V x 8W 0.9 Amp fluorescent fixture; bathroom
-> iPod on inverter, 15W [All day sometimes]
-> Toshiba notebook PC, 60W
-> Gateway notebook PC, 90W

Load Notes
Load is primarily lighting- OFF & ON ~4 hours per night. Usually only one or two is ON at any given time & OFF during movies or games which run from generator now. Lights work great until bed time, but we sometimes do candles if we have a bright batch. One 26W & one 15W lamp are out of commission. iPod 15W AC powered music on inverter during day is 100% solar powered & sounds good. Notebook PCs are not run concurrently, used occasionally during daytime only. Battery usually replenished in less than one full day. One party left 3 lights on all night once & I arrived in the AM to find them dim, but still on. The battery bounced back by the following weekend, despite being abused & old.

Sunset from the deck.
Fire in the chimanea, solar garden lights & mosquito zappers...
...beer, lobsters, & talk of great surf with this incredible view.

Other House "Features"

-> One [1] 5W solar panel to 8-LED spotlight on back patio; added switch to use as needed.
-> Five [5] solar 1-LED garden lamps
-> Two [2] solar mosquito zappers [that really work]
-> Two [2] solar walkway lamps
-> Three [3] battery powered 3-LED push button lamps on ceiling mounts as emergency lighting.
-> Occasional running water, ~500 Gal water tank reserve [cold] that looks like it could collapse the roof when it's full.
-> One Coleman 5 Gal solar shower, good for 2 hot showers.
-> Propane refrigerator [~40 Gal tank chained up outside]
-> Single burner butane stove [20 cans of fuel on hand]
-> Mexican "chiminea" on the wood deck [2 day supply of wood on hand]
-> Two kerosene lamps
-> 1/2 dozen candles
-> 3500W gas generator inside sound-dampened wood box enclosure, muffled exhaust & open on other side for air.
-> 1500W electric heater that runs on generator. [Looking for gas heaters]

bajasurfer · July 2008

Re: Baja Surf Shack

Part Two

Expansion, June 2008
Setup received another 20W panel for 60W total, and we've taken out the old 85 A/Hr battery for new dual 12V deep cycle. Hope was to be able to make coffee & maybe do some 27" TV / PS2 on the inverter, while maintaining good 12V lighting. The out of commission 26W lamp is waiting on new transformer & the 15W lamp is waiting on new bulb. 700W inverter was insufficient for coffee maker...it beeped in agony & turned itself off. Solar coffee will have to wait.

Recently learned calculations reveal 60W is inadequate for 250A/Hr battery support. Need more & bigger panels. I also learned that much improvement was to be found in converting from standard shunt controller to MPPT. Morning coffee maker without the generator must happen as well as occasional TV/PS2 for movies when surf is flat & chica bars become boring.

Convincing the Mrs to spend more on a surf shack 3 hours away from home is the most difficult thing now, LOL.

System Update [June 2008]
Designed by someone who now realizes there is a long way to go.
-> 60W total [~3.34 Amps]. Two [2] 20W panel & two [2] 10W panels, all mono-crystalline Suntech cells. [16AWG]
-> Two [2] new 12V Interstate SRM29 Marine/RV* [Tied together with fancy 1/0AWG]
-> Sunforce 60012 7 Amp Charge Controller** [14AWG connected diagonally]
-> Xantrex 700W inverter [4AWG]

Notes
27" TV / PS2 limited to one night of 3-day stay until we get more solar. Other than that, load will remain as it was under the original 40W system, primarily running the 12V lighting at night & iPod during the day. TV/PS2 are both very old, considered expendable if non-pure sine wave inverter kills them.

*

**

The reason why we're there.

bajasurfer · July 2008

Re: Baja Surf Shack

Part Three

On Tap

We must have solar coffee before this Summer is over. We'll only run coffee maker long enough to brew & keep it warm with the butane stove.

-> SB2512i Charge Controller 25 A 12V MPPT charge controller*
-> 50W [3.05 Amps] panel, mono-crystalline SunWize cells**
-> Total power: 110W @ 12V & ~6.39 Amps.
-> AIMS Power 1000 Watt Compact Power Inverter***

* wind-sun_2010_842799

http://www.blueskyenergyinc.com/pdf/BSE%202512i%20Datasheet1.pdf

**

***

Later On This Year

-> Add 50W [3.05 Amps] panel, mono-crystalline SunWize cells.
-> Question: Would wiring each pair of same wattage panels in series for 24V be a benefit with the MPPT controller?
-> If yes, modify wiring: Paired panels wired in series, all using 14 AWG. 10W+10W, 20W+20W, 50W+50W. Each pairing of panels go to MPPT controller in parallel, yielding 24V from each pairing.
-> Total power: Need math post MPPT. Don't know how MPPT controller will convert the 24V output [normally 160W @ 12V & ~9.44 Amps].

Ultimate Goals For Next Summer

Hardware
-> Add two [2] final panels @ 85W & 5.02 Amps each.
-> Total power: Need math post MPPT. [330W @ 12V & ~19.48 Amps]
-> AIMS 1000 Pure Sine Wave Power Inverter 12V
Targeted Use
-> Run coffee maker [900W], TV [190W] / PS2 [50W] / DVD player [20W], iPod [15W], & lighting [26 to 116W] daily for 3 days in a row without over discharging the batteries.
-> Run web cam from house daily while away, timer turns it off @ night. [28W Camera & 8W Timer]
-> Infrequent remote work via PC / broadband. [58W PC & 45W LCD]

Dave, workin’ it.
thrownin.it.down.jpg

mike95490 · July 2008

Re: Baja Surf Shack

Wow, you have a wonderful "shack" I used google earth, and located it, and will fly down and drink your beer weekdays !! Just kidding, that's a ploy to have you spend more time there on the beach with the 50cal on the surfboard, to guard the "shack"

Seriously - you've done a lot of work, and I hate to say some needs un-doing, but I'll say it anyway. I wish you had found this board some time ago - and gotten advice then.

Many folks are not partial to the Blue Sky controllers, so if you grow past it, check here for other ideas.

You need a serious large panel, using a MPPT controller with 12V panels will not give much boost effect in a warm climate. On hot afternoons, you may not charge at all, as panels heat up, they loose voltage. Playing the game of adding another 20W panel, another 50W panel will leave you with mis-matched voltages (one might be 18.5V, one may be 19.5V and one 17V) and no MPPT controller will be able to make sense of what voltage it should be trying to work at.
Bite the bullet and get something in the 200W 26V ballpark. Stow it inside while gone, and leave the 50W toy panels out to keep the batteries topped off.

You need to keep the batteries CHARGED. When you run the generator, you need to also hook a charger to the batteries to boost them up, Make the AM coffee, run the gennie for 30 minutes, and boost the batteries. Let the solar top them off. The longer the batteries are lower than 95% charge, the faster they die. Read the battery FAQ
http://www.windsun.com/Batteries/Battery_FAQ.htm

Wire the batteries up "diagonally"
http://forum.solar-electric.com/showpost.php?p=12013&postcount=2
http://www.solarseller.com/battery_bank_wiring_diagram.htm
Here's a great writeup on how/WHY to properly wire your battery bank (diagonally)
http://www.smartgauge.co.uk/batt_con.html

Cheap 40A charger - look at Pep Boys for the ~$110 Vector/BlackDecker 4/20/40A charger 1093D. Has selection for deep cycle, and it's a switchmode type of supply, so I think it's new enough to have a good power factor. (700W @ 40A setting)
http://www.amazon.com/review/product/B00009RB0T?showViewpoints=1
Also has equalize and desulphate settings too, truly shuts down with "FULL" reading on display, and fan idles back when done, so it won't boil cells dry.
No battery temperature adjustment or sensor, but it's a ~$110 unit, and will pump 40A safely into a pair of batteries. You are only running it for 1/2 hr in the AM, when the batteries need it the most. Let the solar top it off, and manage the float and EQ cycles.
Connect it diagonally too - on the opposite pair of terminals from your hardwired connections.

As you expand, look into these products:
300W hi eff inverter for the ipods/laptops etc....
http://store.solar-electric.com/mosu300wasiw.html
If you mount it on an thick aluminum plate, that can act as a heatsink to keep it cooler in the hot weather.

400W MPPT charge controller
http://store.solar-electric.com/mosumpsochco.html

Look into LED lamps to replace CFL's as they die, even less power draw.

> Run web cam from house daily while away, timer turns it off @ night. [28W Camera & 8W Timer]
Ouch, that could be a serious drain, 24/7 - what runs the timer - 12V? 120V? internal AA battery ?

Anyway, you HAVE a sweet surf shack, and it's got good potential.
Mike

http://www.mike-burgess.org/PVinfo_1.html

PS
-> Two [2] solar mosquito zappers [that really work]
got a link for a source of them ?

System2 · July 2008

Re: Baja Surf Shack

First, don't buy another small panel. I agree with Mike, you need to undo some of your work. Based on your usage requirements minus the coffee maker, you need to bite the bullet and buy a couple of panels around the 200 watt range.

200w X 2 X 5 hours = 2kwh X .75 system efficiency = 1.5kwh "budget". Three hours of the TV/PS2 will use about half of that budget, two hours on the PC with LCD will use about 13% (do you have to use the 45w LCD or is the PC a desktop?). Lighting will use the remainder.

Your battery (2 of these) http://www.interstatebatteries.com/www_2001/content/products/product_marine.asp is rated at 12.8A at the "15 hour rate". This means you could draw 12.8A for 15 hours, after which your battery would be "dead". Since you don't want to deeply discharge a flooded lead acid battery, you will only be allowed to use half of that capacity. Your battery budget then is 6.4v X 12A X 15hours = 1152 watthours. Since some of your usage will be during the day, the energy being used as it's being produced doesn't have the charge controller and battery charging inefficiencies. With a system like this, you're balancing production and use very carefully and you haven't made any solar coffee yet.

I'd get one of these http://www.walmart.com/catalog/product.do?product_id=9239496 to make coffee since you already have a butane stove.

Operating a system at the edge of it's capability introduces some unintended behavior. Your 900w electric coffee maker will push your inverter and battery to the limit. After inefficiencies are included, the coffee maker will pull about 84 amps @ 12v from the battery at first. As the battery voltage drops rapidly under this load, the amperage draw will increase. The specs for your proposed inverter here http://www.theinverterstore.com/the-inverter-store-product.php?model=pwrb1000# doesn't mention an LVD but operational voltage of 10 to 15v. If it drops to 10v you're looking at about 100A for the coffee maker alone.

Your proposed inverter is modified sine wave, AKA "square". Some devices don't like such a brutal wave form, it swings from -120v to +120v in about 1/1000 second. Spring for a quality sine wave inverter and allow for some growth. It'll take less than a minute to realize "hey, if I had another panel I could run ______ . You'll know you're hooked then.

Not sure what you're looking for in gas heaters but Northern Tool has some http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200332707_200332707 . A friend of mine got one of these http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200339169_200339169 and hooked it up to a 20lb propane bottle, not sure how long it lasts on a tank though. Make sure you buy the correct heater for the type of fuel you're going to use, natrual gas, propane, and butane are all different gases and have different BTU content. Using the wrong gas can be deadly.

Cheers,

Bad Apple

bajasurfer · July 2008

Re: Baja Surf Shack

Hello Mike,
Thanks for being the 1st to review & for offering your feedback.

The neighborhood has gotten visits by patrols of soldiers who hang out all night on the deck of the house next door...there have been rumors of drug deliveries by small boats at night to the beach below the neighborhood...yikes!

Answers to your comments.
<1>
Although it does get hot on occasion, cool onshore breezes are the rule for afternoons where the house is. The wooden mounts I made shield the panels from the dark colored roof enough to feel a temperature differential. I don't know what that's worth, LOL.

<2>
The small panels I started with all share the same construction & were measured at 21.2 to 21.4 V open circuit voltage in direct June sun @ N33° 42' 3" W117°. If a difference between panels of 0.2V is mismatching, then I guess they are mismatched. I thought they were all pretty close, although I didn't plan it that way.

>
I'm returning the 50W panel I have on hand. Thanks for helping me to see that it takes too long to scrub an elephant with a toothbrush.

The current 60W set up will be left as is & relegated to a separate single battery dedicated to the 12V lights & iPod only; which has already been proven reliable. It ran fine on the old 85 A/Hr battery, which is back in the boat now. A new sub-100 A/Hr battery will be put in place of the dual batteries until a system is set up for them.

For the dual batteries, I've started shopping. I'll keep them as sulfate-free as possible until they get deployed again. Please tell me that the 2 batteries won't need more than 370W of panels to eliminate the generator. Arithmetic comes up with 1190W consumed if we run coffee maker [900W x 10min], iPod [15W x 4hrs], 2 lights [52W x 4hrs], & TV/DVD [240W x 3hrs].

<4>
I visited that link about the wiring just before I got the 2 new batteries, and before I found this forum...so the diagonally opposed wiring was done. It's a great link.

<5>
I'm hoping to swap to LED lighting in the bathroom & at least one of the bedrooms. I did a mock run with some LEDs already & our girls said the lighting was too harsh. They did look a bit witchy with the sharp shadowing, LOL. I'm looking for "warmer" toned LEDs.

~$860 spent thus far; includes panels, charge controller, mounting parts/wiring, inverter, & batteries. I figure ~$2K to get it close to right. Solar coffee will have to wait awhile:cool:

Take care, Larry A

bajasurfer · July 2008

Re: Baja Surf Shack

Hello Bad Apple,
Thanks for taking the time to do some math

Percolator!!! You're a genius. I come from a time when TVs used tubes, phone's rotary dialed, & microwave ovens didn't exist, so the fact a percolator didn't occur to me boggles the mind, LOL. That fancy electric coffee maker is headed back to the States!

So, my rough estimate of ~1190 W/Hrs per day drops to ~800 W/Hrs without the coffee maker, iPod, & lighting. A system that will support that level of consumption still means spending way more than originally anticipated, so expectations for this Summer have evaporated, but interest/desire haven't.

I'm looking into two [2] 185W panels on an MPPT controller that should provide enough overhead for ~800 W/Hrs. If Mexico doesn't collapse by next Summer, I expect something will have been installed by then. What's nice is, since the initial setup will remain separate, I can do the dual battery set up from scratch the right way.

Last, a pure sine wave inverter is also on my wish list, but definitely won't happen until the dual battery setup gets redeployed with a sustainable PV system.

Take care, Larry A

bajasurfer · July 2008

Re: Baja Surf Shack

Here, let me do the math in public. Please correct me if wrong, thanks.

Current 60W System
~300 to 360 W/Hrs x 75% = ~225 to 270 W/Hrs generated per day.

IPod 15W * 4 hours = ~60W
Lights @ 52W * 4 hours = 208W
Total = ~268 W/Hrs

Future Separate System (370W?)
~1850 to 2220 W/Hrs x 75% = ~1387.5 to 1665 W/Hrs generated per day.

TV/DVD @ 218W * 3 hours = ~654W
OR
TV/PS2 @ 240W * 3 hours = ~720W
Wall-mounted 12V car stereo @ 50W * 4 hours = 200W
Rarely: Mini-ITX 900MHz 1GB RAM PC @ 58W * 2 hours = ~116W
Rarely: LCD monitor @ 45W * 2 hours = 90W

Possible max utilization 1126 W/Hrs.

Am I getting closer?

mike95490 · July 2008

Re: Baja Surf Shack

> ~1850 to 2220 W/Hrs x 75% = ~1387.5 to 1665 W/Hrs generated per day

Very close. This is how I measure things:

I'll assume 2 ea, 185W panels (I hope you get ones with Vpower max of at least 18V) that will make the MPPT controller happier, or just wire the 2 panels in series, and let the MPPT fix it for you (up to 70V)

185 x 2 = 370 x .8 (STC loss) = 296PV W x 5 solar hours (6 in summer) = 1480Wh/ day
(only if you have perfect panel alignment) Clouds will cut output to 1/5 of sun.

1480 x .8 (flooded cell recharge loss) = 1184 replacement watts to your battery
1184 / 15 (15 being the recharge volts for your battery) 78.9 AH per day replaced

Be very glad you have a propane fridge, that takes a lot of electric requirement out of the system.
Still look at the suresine 300W inverter (600W surge) ($260) It's as efficient as the best mod sine inverters, and much gentler on the electronic wall warts. Mount on thick aluminum plate for extra heatsink

Any thought on if you need any house fans, or does the ocean cool you enough?

PV panels (being the deep blue color they are) get really warm in the sun, best you can do is make sure they are a good 6" off the roof, so air gets under them to help cool them. A breeze helps, but be careful of trying to shield them, they really don't need it. Any shadow will severely cut their output down.

As to the mis-mash of panels
< 1 volt non-matched from different panels is NOT a problem, but a 16V & 19V start wasting power, it goes nowhere, just lost.

Still consider a generator, just so you can preserve/charge the batteries on a cloudy day. The vector can/is designed for ordinary car use, and can be used for the boat battery, recover the neighbors battery etc..

Normally, we'd size a battery bank for 3 days of cloudy weather, and not get batteries below 50%, but you are not making that huge of an investment. Maybe consider 4ea, 6V golfcart batteries for the NEXT 12V battery bank, that would give you a bit more of a buffer. It may be too late now, to consider adding a 3rd 12V battery to the existing system, as the current ones may have aged enough that they are not "new".

I hope you have a good "fuse" or "fuseable" link in the battery system. You don't want the place to burn if you get a short somewhere. Keep the inverter as close to the battery bank as possible, and run the 120V along an extension cord.

System2 · July 2008

Re: Baja Surf Shack

<1>
Although it does get hot on occasion, cool onshore breezes are the rule for afternoons where the house is.

I anticipate a future demand on your system, a fan. :-)

<2>
The small panels I started with all share the same construction & were measured at 21.2 to 21.4 V open circuit voltage in direct June sun @ N33° 42' 3" W117°. If a difference between panels of 0.2V is mismatching, then I guess they are mismatched. I thought they were all pretty close, although I didn't plan it that way.

+/- .2v is probably within the panels' specifications, you'll have very little loss. 1A X 21.2v = 21.2W, 1A X 21.4v = 21.4w. Since the high voltage is dragged down to the lower, in this example, you would lose .2w. Insignificant.

>
The current 60W set up will be left as is & relegated to a separate single battery dedicated to the 12V lights & iPod only...

Your existing 12v DC lighting is a perfect use for your 60w system since there are no DC/AC conversion losses and you wouldn't have to run an inverter (with it's standby losses) all night in case someone needs to turn on a light. However, if I read correctly, your iPod uses an AC adapter. I would move this over to your planned larger system once installed and use the small system strictly for 12v DC. The percentage of the inverter and "wall wart" conversion and standby losses vs. total capacity could be pretty substantial.

If you do a little research on UPS systems you can find small true sine wave units on eBay without batteries dirt cheap. I used them for several years before I got my GTFX. If you go this route, don't get a 2000VA UPS for a 200w load.

Regarding charging your two Interstate batteries, I don't see an "amp hour" specification but the "5 hour rate" is 21A so I'll guess-timate it's about 100Ah each. 200Ah X 12v = 2400watts. Your proposed 2 X 185w panels will probably be able to provide about 280w to the battery (based on my experience with my Sharp 185's). Conventional wisdom says flooded lead-acid (FLA) batteries can be maintained with about 1% of their capacity, in your case, 24w but at that rate there will be no energy left over for consumption (I don't know what the time component to the 1% is). Your proposed array should provide (140w X 2panels) / (100Ah X 12v X 2batteries) = 280W / 2400Wh = 11.667% of battery capacity. That should work very nicely for you.

Cheers,

Bad Apple

bajasurfer · July 2008

Re: Baja Surf Shack

Hello Mike,
Vmp is 24.4V on the 185W panel. I believe that wiring this spec panel in parallel on a 20' 12AWG run should be fine. The controller I'm looking at now is: BZ PRODUCTS MPPT500 500 Watt 45A MPPT.

You're right about the propane fridge...it reduced potential power needs tremendously.

As for ventilation, the house only gets stuffy when we close all the windows & doors. We have a ceiling hole that will be getting a roof vent, but its effect will be minor, since the hole has been open [screened] for some time. Incense smoke flows out the hole swiftly, so there is flow. Day trips away are greeted with near-sauna-like conditions until the windows/doors have been open for awhile. Windows & doors open is the hot ticket & it's so nice out, that it doesn't present a problem while we're on the premises. The drawback is that the batteries are inside, so they are exposed to ~100° temps when the place is all closed up. Oh well.

The new dual battery setup went in last weekend, so it is still pretty new. I can get another battery of the same vintage to up total the A/Hr available to 375 A/Hr. If I were to do this, I'd need to figure out how to add it, since the way it's wired now isn't ménage à trois friendly.

For fusing on the 60W setup, there is a 7.5 Amp inline fuse [bladed type] between the charge controller & the battery. For the new big system, circuit breakers will be deployed.

So far, you guys have helped in two significant changes to everything. No more small panels, & deciding to use a percolator on the butane stove for coffee.
LOL.

Take care,
Larry A

mike95490 · July 2008

Re: Baja Surf Shack

bajasurfer wrote: »

The controller I'm looking at now is: BZ PRODUCTS MPPT500 500 Watt 45A MPPT.

I've not heard any really good things about the BZ line of products. For a 12V, 400W system, maybe someone else more knowledgeable about all the different controllers may chime in. Wait till folks return from vacation on Tues before you decide.

icarus · July 2008

Re: Baja Surf Shack

WARNING, WARNING, WARNING!!!!!! Please do a search and research BZ Mppt controllers! Especially see Solar Guppy's tests and reviews. I have one that has been passed down through other experts for us to test and look at. I would even pay to ship it to anyone!

Tony

PS. Consider building an insulated battery box, so that they are not subjected to such heat, or possible place them in a crawl space. Batteries in a (vented) box , because of their thermal mass take a long time to heat, or cool.

bajasurfer · July 2008

Re: Baja Surf Shack

Hello Bad Apple,

One roof vent is already in the works, & another is being considered. We don't want too many vents, because it gets pretty fricken cold in Winter [low/mid 40°s...and we're nuts enough to be there when the waves are breaking in Dec. The water gets as cold as 54°, your ears ring with a snow cone headache that words can't describe, & you can't grip the zipper of your wetsuit with your purple-colored fingers for at least 20 min after getting out. Enough griping, it's Summer right now!

Your comments on using the 60W system for lights only were welcome. Sequestering the lighting sounds logical, thanks. I'd also like to reduce total wattage of lighting, but not at the expense of light quality. The twin bulb 26W fluorescents give life to the room, so we're not giving those up. The 15W lamps are pretty white, OK in a utilitarian sense.

The dim 8W lamp in the bathroom sucks & it has to go. Preliminary LED tests have given back cold, icky light...perfect for the bathroom so the younger guys who visit don't spend too much time wanking, LOL. The bathroom is getting a new light switch to control 9 LEDs spread 3 each @ sink/mirror, shower entrance, & above toilet. What? ~40W if used 8 hours straight?

iPod will ultimately be put on the "big" system with a pure sine wave inverter. The TV/Gizmo combo takes <300W so a huge inverter won't be needed. TV/Gizmo, recharging laptops & mobile phones, & running tiny form-factor PC will be on site use. Off-site use will be the daytime web cam...still in design stage, but won't use more than 200W/Hrs per day. Heh, I forgot to add that to the math in the previous post. I edited it to reflect this.

Regarding the future system, Mike mentioned adding another battery to up the A/Hr total available, from the 250 A/Hr now for 2 batteries to 375 A/Hr using 3, according to the Interstate SRM29 spec. I don't know if another battery is warranted, but if it is, I'll have to move the batteries from under the kitchen sink. Since it's so hot when we're away, I was thinking of crawling under the house & putting them there anyway...it stays pretty cool under the house & there's air movement.

Thanks,
Larry A

bajasurfer · July 2008

Re: Baja Surf Shack

mike90045 wrote: »

I've not heard any really good things about the BZ line of products. For a 12V, 400W system, maybe someone else more knowledgeable about all the different controllers may chime in. Wait till folks return from vacation on Tues before you decide.

10-4, loud & clear.

bajasurfer · July 2008

Re: Baja Surf Shack

icarus wrote: »

WARNING, WARNING, WARNING!!!!!! Please do a search and research BZ Mppt controllers! Especially see Solar Guppy's tests and reviews. I have one that has been passed down through other experts for us to test and look at. I would even pay to ship it to anyone!

Tony

PS. Consider building an insulated battery box, so that they are not subjected to such heat, or possible place them in a crawl space. Batteries in a (vented) box , because of their thermal mass take a long time to heat, or cool.

Hello Tony,
Mike beat you to the warning on the BZ, but thanks. I'll probably move the batteries to under the house where it's cooler.

Any recommendations on a 400W MPPT?

Thanks,
Larry A

icarus · July 2008

Re: Baja Surf Shack

I don't have one, but everyone here loves the MX 60. Spendy, but will allow a pretty big system.

Tony

PS. Before you write off more CFL's visit :http://www.nolico.com/

More styles and colors and bulb shape than you can shake a stick at. Couple of other things. Get rid of any electric heating loads. Make toast on the stove for example. Cut your loads at the beginning and figure out where you can cut. Finding a 75 watt TV pays dividends over a 125 watt one and so forth.

No matter what you do your loads will grow with time. Consider expandability with every purchase.

BB. · July 2008

Re: Baja Surf Shack

Some of the newer HDTV's are coming down in power usage... This 42 inch one:

Experience leading-edge style, performance and energy efficiency with Philips' Eco FlatTV that was named "Best in Show" in CNET's "Best of CES" at the 2008 Consumer Electronics Show. A dimmable backlight and power saver mode can drive the power consumption of this set down to 75 watts, just a little more than a standard incandescent light bulb, and it has a standby mode power consumption of just. .15 watts. Combining that with a full HD 1080p display, Pixel Plus 3 HD engine and fantastic invisible sound makes this eco-friendly TV delivers powerful performance while helping conserve the future.

Not bad...

-Bill

System2 · July 2008

Re: Baja Surf Shack

...and we're nuts enough to be there when the waves are breaking in Dec. The water gets as cold as 54°, your ears ring with a snow cone headache that words can't describe, & you can't grip the zipper of your wetsuit with your purple-colored fingers for at least 20 min after getting out

I know what that's lke, I've waterskied in every month of the year here in Houston in water as cold as 50F. At least my Nautique has a plumbed in hot water "shower" that makes it oh-so-nice on those cold winter days! You should heat up some water, fill an ice chest with it and drag it to the beach, very nice to soak your feet in after the stinging stops :-)

Cheers,

Bad Apple

bajasurfer · July 2008

Re: Baja Surf Shack

icarus wrote: »

I don't have one, but everyone here loves the MX 60. Spendy, but will allow a pretty big system.

Tony

PS. Before you write off more CFL's visit :http://www.nolico.com/.....

.....No matter what you do your loads will grow with time. Consider expandability with every purchase.

Hello Tony,
That MX 60 is quite a device, but well beyond need & budget alike.

I have a standard fixture I'm going to mount that will use the 11W bulb pictured below:
wind-sun_2063_19156050

This will be going into the bathroom with the 8W tube fluorescent. I decided against the LED idea.

Take care,
Larry A

bajasurfer · July 2008

Re: Baja Surf Shack

BB. wrote: »

Some of the newer HDTV's are coming down in power usage... This 42 inch one:

Not bad...
-Bill

Hello Bill,
Thanks for the LCD idea.
A more humble 26" LCD @ our shack using ~60W will drop daily consumption even further. A Samsung T260 26" Widescreen LCD Monitor.

New power #s

Current 60W @ 3.34A System
· ~300 to 360 W/Hrs x 75% = ~225 to 270 W/Hrs generated per day.
· 12V @ ~90 A/Hrs, AGM battery.
· 3.6% charge to battery A/Hr ratio.
Consumption
2 days & 3 nights normal stay. All loads are 12V, no inverter on this system.
· 12V fluorescent lights @ 67W * 4 hours = ~268W
· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·
· Total likely 268 W/Hrs, 0% during day.
· 5+ days of rest between visits.

Possible Future 140W @ 8.14A System

· 700 to 840 W/Hrs x 75% efficiency = 525 to 630 W/Hrs generated per day.
· 12V x 2 flooded wet cell batteries @ ~200 total A/Hrs.
· 4.07% charge to battery A/Hr ratio.

Consumption
2 days & 3 nights normal stay.
TV options below are much less demanding than the original 27" CRT @ 190W alone.

· 26" LCD TV + DVD; total 75W * 3 hours = ~225W
OR
· 26" LCD TV / xBox360 * 1 hour = ~220W

· 12V stereo speakers @ 14W * 5 hours = ~70W
· iPod on it's own power

· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·
· Total likely 70 to 400 W/Hrs, ~25% during day
· 5+ days of rest between visits.

Nothing is written in stone yet as far as hardware. I'm still getting used to the arithmetic & gaining more awareness about reducing power consumption... like the coffee pot, LCD TV, & as many small 12V-direct loads as possible thanks to this forum.

With the propane fridge, 12V lighting on a separate system, & shrinking power need, the 2nd system will be smaller to match. We'll run on generator until we decide on it. I do know it won't be over 200W...a large high-end PV system on the roof would make the house a target for burglary anyway- it's happened to 2 houses in the neighborhood this year, one of which had 3 large beautiful steeply angled & obvious PV panels on top. The smaller the panels' profile, the better.

Remember, our place is in Baja, & not close to any municipal services...unchecked burglary is, unfortunately, not uncommon. Plus they know most of the Gringos only visit their homes 3 or 4 times a month, leaving them unattended for several days at a time.

Anyway, thanks again for the LCD suggestion.

Take care,
Larry A

bajasurfer · July 2008

Re: Baja Surf Shack

Bad Apple wrote: »

I know what that's lke, I've waterskied in every month of the year here in Houston in water as cold as 50F. At least my Nautique has a plumbed in hot water "shower" that makes it oh-so-nice on those cold winter days! You should heat up some water, fill an ice chest with it and drag it to the beach, very nice to soak your feet in after the stinging stops :-)

Cheers,

Bad Apple

Hello Bad Apple,
Yikes, 50°F is nuts.
We have a 5 Gal solar shower [good for 2 showers] that works a lot better than I thought it would.
Re: feet, I use boots due to rocks, so the feet don't suffer too badly. Looking like shark bait sucks, though. LOL.

Take care,
Larry A

Baja Surf Shack

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