How do I size a battery system and solar system to work effectively?

There are a series of good qualifying questions for sizing a storage system.

A solar system needs to be large enough to recharge the battery or batteries.

The minimum system size for one battery should be: 6 kW

The first two-part question for homeowners:

What do they want to run during a power outage and what do they really need?

When people truly think about it, there is a big difference between the two.

Additionally, we recommend asking these follow-on questions to further assist the customer in making an informed decision:

1] What is your average daily kWh use in winter? in summer?

This question tells you a lot about the rest of the questions - do the math for them. i.e. How long will a Q.Home (12.6 kWh) battery last over the course of ONE day?

2] When your power goes out, how long is it out for?

3] What is your minimum need for the desired period of time?

We recommend choosing 3-4 circuits to power per battery:

- Refrigerator, select lights, bathroom lights, select plugs

4] What is the weather like when the power goes out? (This addresses the ability for solar to recharge the battery during the day - is it winter and cloudy?, or clear and sunny?)

5] What is the homeowner's budget for storage to meet their needs?

This makes them re-think about question 3] and how much back-up they really need

6] After addressing all of the above - How many batteries do they need?

Storage will rarely "take you off-grid" for the typical home. Energy demand for the entire home normally exceeds battery capacity.

NOTE: We only install grid-tied solar. We don't install true "off-grid" solar. We do not typically install back-up natural gas/propane generators.

(As of Spring 2021, generators are in high demand and back-ordered 4-5 months)

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