AS always, it depends on where you live. If you drive one or more EV's that can be a very erratic load from day to day and season to season. I find with 3 EV's that my gross usage is around 8 MWH's a year, give or take. My tot runs around 24-25 MWH's a year, so around 1/3 for the EV's.
Also the cloud cover variance from season to season will very largely with your demographic.... The only way to be over 95% covered is to overbuild your arrays for the low end of exposure. Batteries may or may not have to be increased as well, depends on exact circumstances.
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william fitch
Owner
www.WeAreSolar.com------------------------------
Original Message:
Sent: 04-13-2026 11:19 AM
From: M Keith Sharp
Subject: Designing the Battery-Powered Home - Webinar - Wed April 15
Sorry that I will miss this presentation live. Hope that Smith discusses the value of ambient energy for serving heating and cooling, as well as other loads. Heating and cooling are seasonal, with the consequence that much more generation and storage capacity are needed for some parts of the year if these loads are met with PV. Using ambient energy for heating and cooling leaves loads that are mostly level throughout the year. This allows fewer panels and batteries to serve year round loads.
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M Keith Sharp
Emeritus Professor
Louisville KY
Original Message:
Sent: 04-09-2026 03:14 PM
From: Debbie Coleman
Subject: Designing the Battery-Powered Home - Webinar - Wed April 15
CEU (continuing education units) webinar by GreenHome Institute: Designing the Battery-Powered Home: What Solar + Storage Systems Need to Work in Real Houses
By Greg Smith, author of "The Battery Powered Home"
Residential solar is rapidly shifting from grid-tied systems to solar-plus-storage architectures that support electrification, resilience, and grid interaction. However, many solar battery systems are still designed using outdated assumptions about load behavior, backup expectations, and system sizing.
This course explains how solar PV and battery systems actually operate in modern homes. Drawing from field experience and concepts explored in The Battery-Powered Home, the session examines how system sizing, load management, inverter capabilities, and homeowner expectations shape real-world performance.
https://givebutter.com/BatteryPoweredHomeGHICEUWebinar?mc_cid=6b7d00e832&mc_eid=3156378185
(If you join GreenHome Institute, you are automatically enrolled in the weekly webinars and they keep track of the CEUs for you to make it easy to report on an annual basis.)
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Debbie Coleman
(Architect & ASES Solar Buildings Chair)
Sun Plans
debra28@sunplans.com
https://www.sunplans.comArchitect
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