Best scalable entry for DIY Solar for a home

[RiverMonster]

TLDR; Ready to purchase as a beginner (parts or a kit), but want scaleable parts or kits with the maximum amount of reusable parts that can go into a larger system as I learn and gain skill. Specifically, 1-2 initial PV panel purchases, charging controller, inverter, battery, cables, etc. Enough to go "wow, I can do this", get hooked, and then really dump some cash overzealously into the endeavor.

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I'm sure that this has been asked many times, I scanned the FAQ but didn't see it immediately and am hoping it's just a very short quick answer from the experienced people kind enough to browse.

I have the dream of ultimately powering my home completely via solar (at least during the summer, in IL here), but I'm also a complete beginner. Currently, I am looking to invest in a beginner system and slowly acquire the skills needed while putting regular money into my system to upgrade it over time.

The mistake I'm trying to avoid is wasting money on a tiny system that has little to no parts that can be integrated into a larger system as I grow in confidence and skill. I see many kits and am competent enough to put many of them together without any issue (many lifetimes ago I took a bunch of physics classes, some digital electronics, etc... but have forgotten 95-99% of it) but I know that ultimately a 100, 200, 400-watt kit isn't going to be anything close to the end goal.

We use at least 55 kWh per day and have spiked as high as 65kWh per day. And yeah, it's a long story with multiple work-from-home offices and a stupid amount of electronics running all the time. #lol #facepalm But I'm not looking to put in that 10,000-watt system right now, just learning the basics and establishing my skills and confidence.

Anyway, more to the point, I'd rather pay a premium for overkill parts that can then be repurposed into a much larger system, than items I'd have to sell or toss aside or just relegate to side projects (i.e. nicer charge controllers, inverters, even less but nicer PV panels, etc.). Thus mid-tier or premium parts are the preference. All parts I'd like to source myself and am happy to do so individually even though I will have someone install them on the roof (ultimately, not against a ground-based system as I learn)--because I have an unfortunate case of vertigo. #LOL #facepalm

 

[DThames]

If you buy large (real business) type panels, they are cheaper per watt than smaller panels. The problem is that shipping on large panels will cause a small purchase to be not a good idea. Large commercial type panels can be used on almost any time of system design, so the purchase will be okay moving forward. However, you will need to decide a couple of things before you buy panels. A 60 cell panel might be a little better to cover a wider range of designs but a 72 cell (or even more than 72) be better cost wise if you are serious. I would suggest nothing smaller than 300watts. You will need more than 40 for the power goal of your entire load. So if you could afford 10 or 20 of them up front, shipping would not drive the cost up like ordering a small number several times.

You need to determine if you want batteries for peak shaving or for emergency power. Having batteries govern several aspects of your design. Look at your grid time laws and check with your power company. If your power almost never goes out and your get full credit for what you "sell back", then maybe not a battery. But if you get peak charges and a sell back rate that is way less than the buy back rate, then a battery might be a good idea. Also the cost of power pure KWH influences if a battery is worth the cost or not.

Do you have full sun and space for a large number of panels? Ground mount are easily scalable if you have the space. If you have no shade at all, connecting panels in series has some advantages. For example if the type of inverter you have allows 6 of the panels that you have to be connected in series, you might build a mount for 12 panels, connect 2 series strings of 6 to an inverter large enough to handle 4 series strings. Later you could build another mount for 12 more panels and connect to the same inverter. Later build 2 more mounts, get a new inverter and mount 24 more panels.

If you are not planning a battery, grid tie micro inverters are very scalable. These inverters connect at the panel and you power them with 240v AC off the grid and they do their thing. These support 1, 2, or 4 panels per inverter depending on which one you buy. This is what I have with 8 quad units connecting 32 panels. I built them in 3 steps must like described above, 1/4th, added 1/4, then added 1/2.

I hope that helps, but don't be looking for kits. Learn enough first to decide your path. Some online stores will help you put together a package. Some stores offer pre-planned packages but still you should be pretty sure your path from the start (of purchases).

 

[RiverMonster]

Thanks so much for the heads up on the larger panels and the shipping drawback. I am working to calculate the available roof space now and how many panels I could fit up there, and also how much ground mount space I have available (as well as if I am even able to put up ground mount in the backyard).

I am definitely interested in a battery, and from what I have researched it seems that will not be an issue to scale up. It looks as though adding an extra battery over time, now and then, will be quite possible (with the understanding that I need to take into account monitoring and maintenance, etc.).

I have added researching the whole buyback, rates, peek shaving, issue to my list to research as well.

Thanks again for the reply and info.

 

[nosys70]

the best scalable system is the all-in-one MPPT.
you can set a simple sytem, then stack them.
ideally you want battery and panels for each system, so you also get redundancy.
you can split load per system (totally separated) or merge all of them in one phase (you will need the communication board installed in each MPP.
you can also go split phase or even 3 phase if needed.
For the battery you can start with a row of 280Ah (in 24 or 48) and then add a row in parallel if you need.
going 48V from scratch will be more expensive from start but allow for a lot of power.
Going 24V could be cheaper and well enough, especially if you plan to get 2 or 3 systems.

you want to increase the number of MPP if you need more instant power, you want to increase battery and panel capacity if you want longer duration, With multiple systems you can increase one or the other without problem.