How to Size your Solar Power System

* O link para o vídeo completo está no final desse artigo.
Saiba mais clicando em Robô IQ OPTION de AUTOMATIZAÇÃO de Lista de SINAIS
E conheça também sobre o Melhor Bot Para Opções Binárias 2021
Que tal um robo gratuito para IQ Option? Sistema Para IQ Option Grátis

Does off-grid solar confuse you? Check out my DIY friendly website for solar system blueprints, recommended components and much more!

Join our DIY solar community! #1 largest solar forum on the internet for beginners and professionals alike:

Check out my international best-selling 12V off-grid solar book (Amazon affiliate link):

Coupon codes and solar distributors I recommend:

-Rich Solar: No coupon code needed here because they have the lowest prices around. High quality solar panels and solar generators: Megasite! They have everything you need to build any size system (
10% off code: WillProwse (
10% off code: diysolar (
10% off code: diysolar

-Watts 24/7: Best deals on all-in-one solar power systems, with customer support and distribution here in the USA:

My solar equipment recommendations (Constantly updated unlike my videos! Check here first):

Solar Panels:

Beginner Friendly Lithium Batteries:

DIY LiFePO4 Batteries:

LiFePO4 Battery Cells:



LiFePO4 Battery Chargers:

Solar Charge Controllers:

Solar Panel Mounting Guide:


Battery Monitors:

Favorite Tools:

12V fridges:

-DIY Solar System Packages-

Plug and Play Systems:

400W Starter System:

400W Starter System w/ Alternator Charging:

800W System:

DIY LiFePO4 System Design:

Contact Information:
I am NOT available for personal solar system consult! No exceptions! All emails asking me to design or help with building your system will be deleted. If you are a business or youtuber and wish to contact me, this is my direct email: [email protected]

Join the forum at if you wish to hang out with myself and others and talk about solar

Affiliate information and disclaimers:
Every video includes some form of paid promotion or sponsorship. Links in description are affiliate links. My videos are for educational purpose only. Information is subject to change/update at anytime. Electricity is DANGEROUS and can kill. Be smart and use common sense 🙂

DIY Solar Power with Will Prowse is a participant in the Amazon Services LLC Associates Program,
An affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to
FTC Disclosure Statement:
Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these.

Video Source

Mais Visitados Hoje:

29 comentários em “How to Size your Solar Power System

  1. After reading some of the comments below, I have noticed that we have some new viewers here that have not watched my other videos. Many of my efficiency and irrandiance equations are covered in other videos and my book. The video above is great for estimating how much power you need, but you can go much, MUCH deeper into these equations. My book covers various losses in a system, battery efficiency and more.

    If you want to calculate total system efficiency, watch this video:

    If you want to learn more about faradaic or coulombic efficiency of batteries, watch this video:

    If you want to learn about cost of a battery with factoring in charge cycle life (which can make expensive batteries look cheap, and cheap batteries look expensive in the long run), watch this video:

    I hope this helps! This video is GREAT for estimating a solar battery and array here in the united states, but if you are near the poles or dealing with local climate conditions that limit solar, you will need to watch my other videos to calculate your system. Also, the SCC needs to be rated at the OUTPUT, with the working voltage of panels or the nominal voltage of battery bank. Voltage open circuit is for sizing the SCC input voltage and headroom figures. Different equation thats covered in my other videos and book as well. In great detail.

  2. Why wouldn't you jump the voltage up to about 120vdc to a 80A MPPT to charge the battery pack? For the 10 KWh solar array?

  3. Hi Will, Thank you for making these videos. As a city dweller in Ohio I know lots of people who want solar power. From your videos I always recommend a grid tied 48 volt system, with as many panels as they can fit on their roof. Being in the city even with a small bit of land, theft is a factor. That makes ground mounting an issue. Any rate, I am curious, if I use 562KwH on average per my bill, and install a 10,000Kw grid tied solar array (let's assume no batteries) am I doing more harm than good?

    In more words.
    Should I try to spec my system to be all I need? Or, if I have the funds, should I set up my system to feed back into the grid?

    I hope my questions made sense. I am not a wordsmith.

    I am just a basic American human who wants a grid, but also thinks it's possible for me to over buy and feed into the grid as help, not a hindrance. I mean, electricity is only theory.

    Also, for myself I will have batteries for my needs, but would be feeding back into the grid during peak hours.

    Side Note: just as I pay in taxes and license fees for roads. I don't mind paying transmission and distribution fees to keep the grid up.

  4. Consider ferrulite heated and the discharged through a stirling engine electric generator. A night storage heater effectively. I am moving to Portugal next week setting up my homestead and this system is going to be part of it all going on my channel.
    The point I would make is its low tech with charge discharge cycles running into the millions. Ferrulite is iron oxide iron ore basically.
    One additional solution is demand side management eg running high power devices such as a washing machine during the day.

  5. You are so great at making things simple.Thank you. I wish you were my Son…you are my sunshine…anyway.Go SUNS!!

  6. To the whacko liberals, "rule of thumb" refers to something done based on actual practice and experience rather than theory".

    Much like the OK hand gesture, where liberals went off the rails claiming it stood for white power when it has no connection to racism, then photos of Obama, Hillary, Biden pop up of them doing the ok symbol and the liberals shut up about it.

    Great videos, I love your content, I seen the comment from the whacko liberal making racist narratives about your video and the rule of thumb so I wanted to illustrate the facts.

  7. I’m trying to run two automotive fans 80w each basically when sun is up I got two panels and battery and 30amp charge control

  8. So To power my refrigerator (517W) completely off grid, I got like 8-12 300 ah batteries with 3 days autonomy. Plus the solar panels to match a 8-9KW. That’s like a 30-40K just to run 1 thing.

  9. you are great but your talking over my head, how many 12 v battery's do i need and what strength solar panels do i need. I am old and grey an trying to fix up my sm. travel trailer parked on my property for self containment purposes for when the SHTF. I want to run a tv, recharge power tools and battery powered appliances. please if anyone can help i would appreciate it.

  10. Hey Will, I really want to work with you in establishing a solar project. What's the name of your website, book, social media handle or email, so I can reach out, that is if you're interested.

  11. could you do one on how to plan a solar system to supply the electric to an electric fence? Guess we're in joules instead of kwh

  12. Hi Will, is it necessary also in hybrid inverters like mppsolar 3kw or 5kw ? Thanks

  13. I live in South Africa and we get like 10hours of good sunshine a day regardless of time of year . Yet we still over size the panels we use. I wonder why??

  14. I have recently found your channel and am very excited. I have just begun to be interested in solar power and have just retired at 65. I have an insatiable desire to learn everything about solar power and electricity. I do not know where to start with your videos. Jumping around is rather confusing. Thank you for information on the website. I am also considering taking a course at our local Technical College in basic Electrical Power and Control. I really want to understand what I am doing. You have charged me to learn this. Thank you.

  15. Just tell people that W (watts) = A (amps) * V (volts) or W = A * V. Now in engineering we use P (power) = I (Intensität (german for intensity)) * E (electromotive force) or P = I * E. That is all you need to know except H = hours and K = kilo or 1000. So 12 Volts * 100 Amps = 1,200 Watts or 1.2 K Watts. If you use 1.2 K Watts for 1 hour you use 1.2 KWH (kilo * watts * hours).

  16. im assuming theres a different computation if your sytem is grid tie, no batteries used and you want to have the minumun panels used to supply your daylight demand. if u havent posted this video please do ill watch thank you

  17. I just put 4 x 355w sunpower panels I got for free on my ambulance with 2 x 60amp solar controllers on 2 x 280ah lifepo4 batteries on a 3k inverter charger. Can run my 9k btu mini split heat pump all night…. in fact I have plugged the van in in over a week and interior temp hasn't gone above 72. Help the fridge not cycle much.

  18. Excellent thank you. And i estimate that you are at least twice as intelligent as I am in order to be able to explain this in a way that I understand lol lol And I'm not an idiot I do hold a Ham Radio Tech license for example… BBA degree (Bach Bus Admin) so I'm not stupid but you are very bright young man.

Os comentários estão encerrados.