Solar Photovoltaic (PV)4 / 18
PV Economics & Payback
Cost per Wp, FiT/export income, payback period, 25-year lifetime value.
10 min read · Jacob Willis, Net Zero Lead · Last reviewed July 2026
PV is now a mature, low-risk investment, but whether a specific system pays depends on its cost, how much of its output is used on site, and the value of the electricity it displaces. Because the technology is so reliable, the financial risk lies almost entirely in these price and usage assumptions rather than in the panels. This lesson covers the cost side, the value side, a worked example, the 25-year view, and what strengthens the case.
In this lesson
- 01The cost side
- 02The value side
- 03The 25-year view
- 04Sources and further reading