If you might add an EV, more appliances, more people, or heavier heating/cooling in the next 3–5 years, plan expansion now — retrofitting an undersized platform costs more than sizing the infrastructure correctly upfront.
Prevention approach:
- Modular inverter/battery platform (e.g. Sigenergy) that accepts add-on modules
- Oversized solar array for future load
- Battery sized for today, expandable tomorrow
Simpler only makes sense when usage is genuinely stable — no family change, no EV, no new heavy loads. Most households grow energy demand over time.
100UP’s default: plan for expansion. Lower cost now, fewer expensive regrets later.