System Energy Audit and Sizing Spread Sheet

System Energy Audit and Sizing Spread Sheet 2021-01-29

noob says "thank you" - gotta start somewhere!
Very nice and useful spreadsheet
This has been so tremendously helpful for planning my system, thank you! Curious about why "# of days to recharge while under load" is a user input. How am I determining the answer to this question? Shouldn't this spreadsheet be able to tell me that?
FilterGuy
FilterGuy
>Curious about why "# of days to recharge while under load" is a user input.
> How am I determining the answer to this question?
> Shouldn't this spreadsheet be able to tell me that?
It is asking how quickly the user wants the system to recharge from fully drained and then uses it as an input to determine solar panel sizing. Some users will want just one or two days, others might be willing to wait more days to fully charge.
The alternative is to ask the user for Solar Panel size and then calculate the number of days it will take to recharge, but that would kinda defeat one of the purposes of the spreadsheet.
Very thorough, incredibly detailed, and you spent a lot of time. Might be easier to just plug in information from Electric Bill?
very helpful
Firstly, this spreadsheet is gold, thank you so much for this resource.

Secondly, I'm a bit confused. Shouldn't the "Required Total daily Solar output (Sunny)" - cell L19 calculation which looks at the "# sunny days to recharge (from ZERO) while under load" - cell L18 (as you mention in your definitions, it is the number of sunny days required to recharge the battery from ZERO (or in this case assuming from max discharge) while you are still using power) be referencing the "Battery capacity" - L14 x "max. discharge" - L11 as well as the "Daily Storage Requirement" - cell L10)? You are only considering daily requirements and not replenishing the entire battery in your current formula.
You have: L19 = L10+ L10/L18
Should it not be: L19 = L10+ (L14*L11)/L18

If I'm wrong I may need an explanation why you are not referencing the battery's capacity in a. calculation to full recharge, where a recharge is directly dependent on how much of the battery has been depleted on not only on your daily usage.

Cheers.
FilterGuy
FilterGuy
Good catch!!! I fixed it yesterday. Sorry it took so long
Awesome..Thank you very helpful.
Brilliant, thank you!
Thanks for making this available, great resource.
Top