Check my plan?

[chumpy36]

I made this plan with Gemini AI. I have a garage apartment that is being finished. I will have room for about 10 panels on the roof. The apt has a subpanel connected to the main panel in the house. I want to be able to be able to use the solar to offset my costs. Batteries and a hybrid inverter will allow me to have some backup power in case of grid power failure. Is it reasonable to use the main and subpanel as the critical load panels? Just turn everything else off and just power the circuits I need? Of course I will have a transfer switch on the service entrance. Can you take a look? Would love recs on any of the hardware as well. Dog pic for visibility and tax purposes.

Thanks

System Overview

• Goal: Reduce electrical costs, achieve energy independence, and have a robust backup power system.
• Location: Atlanta, GA (no net metering)
• Solar Panels: 10 high-efficiency monocrystalline panels (around 400W each)
• Inverter: Hybrid inverter with integrated ATS (e.g., Sol-Ark 12k)
• Batteries: Lithium-ion (LiFePO4) battery bank (e.g., Blue Planet Energy, SimpliPhi)
• Generator: Existing generator with inlet box on garage subpanel
• Transfer Switch: Manual transfer switch at the service entrance
• Critical Loads Panels: Main panel and subpanel
• Monitoring: Inverter-integrated monitoring and optional add-on systems

Hardware Recommendations and Estimated Pricing

System Overview

• Goal: Reduce electrical costs, achieve energy independence, and have a robust backup power system.
• Location: Atlanta, GA (no net metering)
• Solar Panels: 10 high-efficiency monocrystalline panels (around 400W each)
• Inverter: Hybrid inverter with integrated ATS (e.g., Sol-Ark 12k)
• Batteries: Lithium-ion (LiFePO4) battery bank (e.g., Blue Planet Energy, SimpliPhi)
• Generator: Existing generator with inlet box on garage subpanel
• Transfer Switch: Manual transfer switch at the service entrance
• Critical Loads Panels: Main panel and subpanel
• Monitoring: Inverter-integrated monitoring and optional add-on systems

Hardware Recommendations and Estimated Pricing

|| || |Component|Recommendation|Estimated Price| |Solar Panels (10 x 400W)|Trina Solar, REC, Q Cells|$4,000 - $6,000| |Hybrid Inverter|Sol-Ark 12k|$5,000 - $7,000| |Batteries (10 kWh)|Blue Planet Energy, SimpliPhi|$8,000 - $12,000| |Combiner Box|MidNite Solar, Schneider Electric|$500 - $1,000| |Racking and Mounting|IronRidge, Unirac|$1,000 - $2,000| |Wiring and Conduit|Varies based on length and type|$500 - $1,500| |Manual Transfer Switch|Reliance Controls, Generac|$500 - $1,000| |Installation (Electrician)|Licensed electrician|$3,000 - $5,000| |Total Estimated Cost||$22,500 - $35,500|

Additional Costs:

• Permitting fees
• Battery monitoring system (optional)
• Smart home energy management devices (optional)

System Design and Installation

1. Detailed Design: Work with a qualified solar installer or use online design tools to create a detailed system layout, including panel placement, wiring diagrams, and component specifications.
2. Installer Selection: Get quotes from multiple reputable solar installers.
3. Permitting: Obtain necessary permits from your local building department and utility company.
4. Installation:

• Hire a licensed electrician to install the inverter, batteries, combiner box, transfer switch, and wiring.
• Ensure the electrician is experienced with solar and battery backup systems.

1. Commissioning: Test the system thoroughly to ensure proper operation.

Key Considerations

• Battery Capacity: The estimated 10 kWh battery capacity is a starting point. Adjust based on your desired backup time and energy consumption.
• Generator Integration: Ensure the generator is properly sized and interconnected with the transfer switch.
• Load Management: Prioritize essential circuits during backup periods to conserve battery power.
• Monitoring: Utilize the inverter's monitoring capabilities and consider additional monitoring systems for detailed insights.
• Safety: Always prioritize safety and follow electrical codes and best practices.

This comprehensive plan provides a roadmap for your DIY solar project. Remember that costs and specific components can vary, so get professional quotes and consult with experts throughout the process.

By following this plan, you'll be well on your way to achieving your goals of lower energy costs, energy independence, and a reliable backup power system.

 

[fwunder]

What is your real or estimated energy usage? Kinda critical to know. I have a 2800 sq. ft house and only use ~20 kWh per day average. I have neighbors with same size house who use 100 kWh+ per day.

 

[SunDave]

If interested in Sol-Ark look into a Sol-Ark 15k instead. I have one, and have been happy with it. More robust for not much more cost. Allows a full 200 amp panel to be put on the load terminals since the unit has a 200amp pass-through. Make sure to get batteries that you can have a UL listing on as a combo with the inverter. It can help with permitting and compatibility.

I would strongly recommend doing the majority of your research outside of AI queries. They can be wildly inaccurate, and this forum is getting littered with them. It may help to state what you plan to run with this, instead of explaining the equipment. It is kind of jumping to the solution instead of giving someone a use case to work off of. There are likely cheaper options if you don't want to back everything up.

With a 15k, and some others in a similar category, you may not need a critical loads panel. Always a good idea to include a transfer switch, so you can go to grid power if something goes wrong.

Most utilities will not like that you have an inverter capable of back-feed unless you have a grid tie agreement with them. There are inverters that won't back-feed, but they operate slightly differently.

As fwunder said, it is best to start with how you will use it. To get an idea of what equipment category is in the ball-park.

------------

Often ignored is that any equipment will have a base energy usage. The smaller your system is, the higher percentage of the power you create will be used by the equipment itself. That is one more reason why it is important to right size each part of the system to match what you want to do with it.

 

[timselectric]

I made this plan with Gemini AI.

Well, that was a waste of time.

 

[fwunder]

Often ignored is that any equipment will have a base energy usage. The smaller your system is, the higher percentage of the power you create will be used by the equipment itself. That is one more reason why it is important to right size each part of the system to match what you want to do with it.

It is fun to see how small the footprint of my two Victron 5 kVa are.

 

[k490]

Why would you use a transfer switch if your planning on interconnecting with the utility. Your inverter would back feed to the homes main service panel after the meter using a solar breaker. That way solar energy is being used 100% of the time when the panels have sun either going to the battery for storage for use after dark, or loads that are on at the time. Think of solar like a gas generator don't want the gas engine burning gas while it's powering a 20 watts of LED lights.

I would learn more about how all this works before you buy anything, or just get quotes from a solar contractor who can install it for you. Don't buy anything until the permit and utility have approved your plans.

 

[chumpy36]

What is your real or estimated energy usage? Kinda critical to know. I have a 2800 sq. ft house and only use ~20 kWh per day average. I have neighbors with same size house who use 100 kWh+ per day.

40kwh a day roughly

 

[chumpy36]

If interested in Sol-Ark look into a Sol-Ark 15k instead. I have one, and have been happy with it. More robust for not much more cost. Allows a full 200 amp panel to be put on the load terminals since the unit has a 200amp pass-through. Make sure to get batteries that you can have a UL listing on as a combo with the inverter. It can help with permitting and compatibility.

I would strongly recommend doing the majority of your research outside of AI queries. They can be wildly inaccurate, and this forum is getting littered with them. It may help to state what you plan to run with this, instead of explaining the equipment. It is kind of jumping to the solution instead of giving someone a use case to work off of. There are likely cheaper options if you don't want to back everything up.

With a 15k, and some others in a similar category, you may not need a critical loads panel. Always a good idea to include a transfer switch, so you can go to grid power if something goes wrong.

Most utilities will not like that you have an inverter capable of back-feed unless you have a grid tie agreement with them. There are inverters that won't back-feed, but they operate slightly differently.

As fwunder said, it is best to start with how you will use it. To get an idea of what equipment category is in the ball-park.

------------

Often ignored is that any equipment will have a base energy usage. The smaller your system is, the higher percentage of the power you create will be used by the equipment itself. That is one more reason why it is important to right size each part of the system to match what you want to do with it.

Not sure what you mean by how I'll use it? The goal is to lower my monthly usage from the utility and also provide a backup in case power goes out. In that case, I'd like to have generator input as well as the solar to help power my needs while the power is out. Is that what you mean? Thanks for the reply!

 

[chumpy36]

Well, that was a waste of time.

I don't think so. It actually answered several of my questions that I haven't been able to get out of humans. I think the plan gave me a good starting point.

 

[chumpy36]

Why would you use a transfer switch if your planning on interconnecting with the utility. Your inverter would back feed to the homes main service panel after the meter using a solar breaker. That way solar energy is being used 100% of the time when the panels have sun either going to the battery for storage for use after dark, or loads that are on at the time. Think of solar like a gas generator don't want the gas engine burning gas while it's powering a 20 watts of LED lights.

I would learn more about how all this works before you buy anything, or just get quotes from a solar contractor who can install it for you. Don't buy anything until the permit and utility have approved your plans.

Don't you need a transfer switch to disconnect from the utility precisely because you would backfeed the grid? Maybe hurt a line worker? I am in the learning process now, thus this post. But I do have construction going on right now so I do need to figure out where to put everything and run lines.

 

[SeaGal]

Well, that was a waste of time.

I don't think so. It actually answered several of my questions that I haven't been able to get out of humans. I think the plan gave me a good starting point.

- Tosh! You obviously didn't ask the right type of humans in the first place then. And anyway, you got a load of gibberish that's been cobbled together by an engine that only 'knows' about statistics... and then come on here asking the humans what to do!

 

[AH Trimble]

40kwh a day roughly

Depending on the outlined system for back-up...
With only 10kwh of batteries and 4kw PVs...do the math.
It is showing averaging 1.6kw per hour throughout the entire 24-hour day. That only gives you about 6 hours of power in low/no PV production with fully charged batteries running them down to 0% SoC.

Also, Sol-Ark 12k's have been know to have considerable problems, and Sol-Ark is struggling with their customer / tech support. Rumor has it they are also struggling financially.
I also noticed that the AI genius didn't include professional install of the PV's. Is that something you would do?

I would forget the AI and gain knowledge, then decide on quality components, right-sized system, trusted installer that can also handle the permitting. And doing so, the $35,000 would be a decent bottom end price.

There are plenty of folks on here that are willing to help out. Touch base with them and most will step up for you.

 

[SunDave]

Not sure what you mean by how I'll use it? The goal is to lower my monthly usage from the utility and also provide a backup in case power goes out. In that case, I'd like to have generator input as well as the solar to help power my needs while the power is out. Is that what you mean? Thanks for the reply!

No problem. It's good that you have an estimated total load (roughly 40kWh a day) but there is also the how it is used. The size of equipment that would work is different if you plan to run an electric dryer, use cooking appliances and run an AC unit, vs. just some lights and an internet router if the power goes out.

Don't you need a transfer switch to disconnect from the utility precisely because you would backfeed the grid? Maybe hurt a line worker? I am in the learning process now, thus this post.

There are devices that are capable of backfeed, and ones that are not. It is good to pick if you plan to sell back to the utility before making a purchasing decision. They are two different worlds equipment wise.

It is a good idea to have a transfer switch no matter what. That way if something ever goes wrong with the solar equipment, you can take it out of the loop and use directly from grid. There are cases where sub-panels are involved too, so it is impossible to know the exact best solution without knowing a lot of variables.

I would caution that DIY solar is a long process of learning. Not many people have a robust and cost effective system the first time they design one. You are starting in the deep end of the pool so to speak, so it would be easy to make a mistake.

One possibility would be to plan in an easy way to add the solar, and not rope it in with the time crunch of the rest of the project. For example, add a way for wires to get to the roof (that's a lot of research on it's own for code, etc.), and also set up a transfer switch and spot for the future inverter, and batteries. You could pave the way to easily adding the solar, but yet give yourself the time to play around with a small system, or learn the ropes first.

Just one idea. Good luck with whatever you decide.

 

[fwunder]

40kwh a day roughly

So i'm guessing your current electric bill is $200-$300 /mt? Just curious if you've done any ROI? I know when I did, I found that there was no way I could justify the expense but, I really liked the idea and it's fun for me! If I simply wanted to defray electric bill, I would try ( impossible ) to convince my wife to not use her hair dryer, her electric tea kettle and hang clothes on a line. That said, welcome to the adventure !!