diy solar

diy solar

DIY Checklist

svetz

Works in theory! Practice? That's something else
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Looking for help reviewing a wiki page to capture a general checklist to help solar newbs navigate capturing the sunshine.

Any gotcha's not on it you wish you'd known about before starting?
 
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11. Battery low/high voltage cutoff

11. Battery low/high voltage and temperature cutoff

New Items:
20. Purchase all the necessary tools ahead of time. Some tools are hard to source locally.
21. Replace inefficient, high consumption appliances with more efficient models.

(For me, there were tools I had to buy at the last minute. Only one was found locally. Similarly, there were supplies I needed at the last minute that were hard to find locally, such at large gauge lugs.)

Word Smithing:

6. Build a rough economical model to understand payback (or use SAM's)

6. Build a rough economic model to understand payback (or use SAM's)
 
11. Battery low/high voltage cutoff

11. Battery low/high voltage and temperature cutoff

New Items:
20. Purchase all the necessary tools ahead of time. Some tools are hard to source locally.
21. Replace inefficient, high consumption appliances with more efficient models.

(For me, there were tools I had to buy at the last minute. Only one was found locally. Similarly, there were supplies I needed at the last minute that were hard to find locally, such at large gauge lugs.)

Word Smithing:

6. Build a rough economical model to understand payback (or use SAM's)

6. Build a rough economic model to understand payback (or use SAM's)
Great changes, got them all in.... thank you!
 
Here's some ideas that popped up in my thinking while reading the list...

>9. Ability to measure power from/to: Panels, house, Batteries, grid
In my case, I measure inverter output vs PV input to get a sense of inverter efficiency (I'm running 84%). Suggest 'inverter output' to the measurement list unless that's included in 'house'?

>17. Building Code
Suggest all components, boxes, equipment, circuit breakers, etc... be ETL or UL listed. My jurisdiction required this for inspection and I was told that a Home Fire insurance claim might fail if they find non-ETL/UL stuff.

Suggestions to add
- Battery "Fire" Containment box/metal-cabinet/plan + fire extinguisher - especially for lithium-ion.

.- Lightning arrestors (surge suppression) for the panels
 
Probably want to have all the BIG issues handled right up front, some are not based on "logic" but can still be show stoppers:

2.5) investigate local government regulations BEFORE you start. In many areas you will not be allowed to actually do anything yourself; you must have a "licensed solar contractor" handle everything. In some areas homeowners can pull permits but not always.

a few others thoughts:

item 4, annual shade patterns is well, kind of subtle...most people do not realize that a "tiny" bit of shade in the corner of a panel can shut the entire panel down. Consider: Annual shade patterns are critical; panels require full exposure to sunlight, even a very small amount of shade may disable a solar panel depending on make and model.

move item 7)panel size/quantity up towards the top 5 as it can drive the decision for roof or ground mount which is a big decision (roof would require not only an assessment of current roofing tile remaining life, but can the roof itself handle the structural load); this could be another show stopper...

somewhere in the planning area consider:
X) determine if lightning arrestors are appropriate for your installation choice and, depending on your area, is an external lightning protection system warranted
 
Thanks! I've incorporated all of those suggestions with the caveats below...

>9. Ability to measure power from/to: Panels, house, Batteries, grid
In my case, I measure inverter output vs PV input to get a sense of inverter efficiency (I'm running 84%). Suggest 'inverter output' to the measurement list unless that's included in 'house'?
Please double-check #9 to see if the changes are adequate...

Lightning arrestors (surge suppression) for the panels
It was already covered in #12, unless you mean something beyond that?

2.5) investigate local government regulations BEFORE you start. In many areas you will not be allowed to actually do anything yourself; you must have a "licensed solar contractor" handle everything. In some areas homeowners can pull permits but not always.
Split #3 into a few sub-bullets... see if you think that covers it. Ditto #4

...move item 7)panel size/quantity up towards the top 5 as it can drive the decision for roof or ground mount which is a big decision (roof would require not only an assessment of current roofing tile remaining life, but can the roof itself handle the structural load); this could be another show stopper...
Did some rewording there so the interaction is hopefully all contained in #7 without any shuffling.
 
Split this out into it's own reply as I think it needs a lot more discussion:

- Battery "Fire" Containment box/metal-cabinet/plan + fire extinguisher - especially for lithium-ion.
I added #22, but I'm not happy with it... mainly because I don't think there is a good answer to "what to do if your batteries catch fire". A fire extinguisher or metal box isn't going necessarily going to cut it AFAIK... see The Morris Fire: Extinguishing Lithium Battery Fires. Currently, my plan is to hope it doesn't happen, they're bolted onto the wall and if they catch fire I have no way to put them out.

Thoughts?
 
The other comments - great, thanks for considering them :)

Split this out into it's own reply as I think it needs a lot more discussion:


I added #22, but I'm not happy with it... mainly because I don't think there is a good answer to "what to do if your batteries catch fire". A fire extinguisher or metal box isn't going necessarily going to cut it AFAIK... see The Morris Fire: Extinguishing Lithium Battery Fires. Currently, my plan is to hope it doesn't happen, they're bolted onto the wall and if they catch fire I have no way to put them out.

Thoughts?
I've read several discussion about building battery boxes to contain 18650(s) because if 1 starts it will likely ignite the ones next to it. The ultimate conclusion is to have a battery box/shed *outside* the house. But mine are not contained and I'm not sure I'm that worried since the cells in my powerwall are low C (200ma/cell) and charge/discharge in the middle of the voltage range (4.0v to 3.5v).

I only mentioned the topic since there seems to be so much discussion on it at various places. In particular in relation to 18650 (as apposed to LifePo4).

Maybe the key point is something like: "There is some fire risk with lithium-ion batteries and its worth considering mitigation strategies that fit your situation." I know - I like your comment better than mine :)
 
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Hopefully, some more members will chime in. My thinking is to delete #22.

Here's a link to a fire safety test on the Tesla Powerwall, they simulated a cell in thermal runaway and their engineering handled it. They were able to set fire to it with an external fire:

NFPA concluded that a prolonged fire outside the Powerpack could definitely induce the Powerpack into thermal runaway, but they found that the consequences were confined to the pack and didn’t propagate...

On the other hand, a lot of members building their own DIY packs may not have considered any fire safety.
 
Semi Related:
A) How to ask a question !
- Provide General Location (Country/state/province & nearest major city)
- Provide Make & Model of equipment in question - provide link to product when possible.
- Ask a clear question with a description, not just "it won't work".

B) DO NOT BUY ANYTHING until you have a Plan !
- There are NO Once in a LifeTime Deals that "must" be purchased right away, deals happen all the time.
- Local Rules, Regulations and Codes must be checked so your plan can be carried out. Prevent Shocking Surprises !
- Be Patient, take the time to learn & understand, and do not make assumptions (they are almost always wrong).
The old adage is very true: "A Failure to Plan, is a Plan to Fail." Most often it is quite costly and potentially dangerous.

Unrelated, not sure would it would fit in actually, people talk about Battery Pack / Bank Containment options.
A Pack itself is one beast but multiple packs in a bank is yet another. Traditional Boxes for Lead Acid Batteries can work depending on what they are made of, some of which are not fire-resistant let alone fireproof. Some people are using Fireboard (the concrete variety) which can be a bear to deal with and has it's own issues such as moisture retention. There is an Alternative Board manufactured with Magnesium Oxide which is often referred to as Mag-O Board. It comes in 4'x8'x1/2" sheets, can be cut with a standard circular saw (don't waste a carbide blade on this, it will kill it) and screwed together with coarse drywall or wood screws. This can be used as a Heat Shield for fireplaces, woodstoves as well as a water-resistant tile backer for floors & walls as well. Also, it is about 1/2 the cost of Cement Fireboard and is available in Big Box stores.
REF LINK: https://mgosystems.com/faqs/

I think some clarification somewhere as many people come in with Lead Acid experience and of course have THAT knowledge which does not necessarily cross into Lithium Land. For example, adding battery packs to a bank over time. With Lithium we can add packs over time UNLIKE lead which will always be drawn down by the weakest battery and the whole battery aging thing which does not apply the same. This is often a Big Whallop because if people think, Ohh I have to get 30kWh of storage and all at once that's a Big Pile of Dough all at once, not realizing they could do it in 10kWh incremements over time if they wanted to. The initial "shock" factor can not only put a Bad Taste "1st impression" but can & does scare some folks away. I feel THAT should be addressed boldly and blatantly for newcomers.

Just some ponderances. Hope it's useful.
Steve
 
...
A) How to ask a question ! ...
B) DO NOT BUY ANYTHING until you have a Plan ! ...

Part "A" sounds more like for the forums rather than a DIY Installation
Definitely agree with part "B", but that's what the checklist is essentially about... hopefully paragraph 1 in the entry makes those sentiments clear.

... people talk about Battery Pack / Bank Containment options. ...
Now that's a good point... we could delete #22 and modify 17.3... I'll do that... let me know if you all think that covers it.

... Traditional Boxes for Lead Acid Batteries... There is an Alternative ...... can be used as a Heat Shield ...
Wow! That could be a wiki entry in itself! Someone should write one (hint hint, wink wink, nudge nudge ;) ).
 
Wow! That could be a wiki entry in itself! Someone should write one (hint hint, wink wink, nudge nudge ;) ).
Who ME ? IF you'd have included the Eh Whut ! I would'a pondered it.
Well THAT would be a first, to have something I submitted posted & made into a Sticky or Reference proper...
I have spent a lot of time writing stuff that just got lost in the moosh...

Every few days someone pops in with "Ohh I went and bought A,B,C, D and now how do I make it all work"... I don't even look anymore, it's always a lose lose.

note, I'm not a MOD never asked or wanted to be one so I don't have to be responsible for anything, including stickying etc... hehehe... BTDT not again.
 
Who ME ? IF you'd have included the Eh Whut ! I would'a pondered it.
Well THAT would be a first, to have something I submitted posted & made into a Sticky or Reference proper...
I have spent a lot of time writing stuff that just got lost in the moosh...

Every few days someone pops in with "Ohh I went and bought A,B,C, D and now how do I make it all work"... I don't even look anymore, it's always a lose lose.

note, I'm not a MOD never asked or wanted to be one so I don't have to be responsible for anything, including stickying etc... hehehe... BTDT not again.
To me, what was really valuable was to start small - 400w PV, EPEVER, and small 24v 18650 - and then grow to 12.8kw PV in 3 stages. So rather than try to plan all at once up front, when dealing with so many topics that just don't make sense (in your gut) till you've actually had hands-on, is to perhaps start small and then expend? Not sure that would fit in this type of list, but it's my reaction to 'plan everything first' :)
 
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