Best direction & angle
Two things decide how much your panel makes: direction and tilt. In the U.S., south-facing captures the most sun across the day; east or west each lose roughly 15–20% but still work.
The ideal tilt is roughly your latitude — about 30–40° for most of the U.S. A steeper angle helps in winter when the sun is low; a shallower one helps in summer.
Balcony reality: many railings force a vertical (90°) mount, which produces noticeably less than a tilted panel — often 20–30% less. If you can use a stand or tilt bracket, do it.
Avoid shade at all costs: even partial shade on one part of a panel can cut output sharply. A clear, sunny, south-ish view beats a perfectly-angled but shaded spot every time.
Related guides
How plug-in solar works · What you need to start · ROI & payback · Installation basics · Battery storage · The 800W limit · Panel direction & angle · Plug-in solar for renters