Tidal Energy ROI Calculator

Tidal energy generates electricity from predictable tidal flows. Capacity factor 30-45% (much higher than solar at 10-15% or wind at 25-35%) because tides are predictable. Installation cost 4,000-8,000 per kW capacity. Operations cost: 2-4% of install/year. Lifespan 20-30 years with refurbishment.

10M install for 1MW capacity. 35% capacity factor × 8,760 hours = 3,066,000 kWh/year. At 0.15/kWh wholesale = 459,900 annual revenue. 300k maintenance. Net 159,900/year. Over 20 years: 3.2M total. Negative ROI vs install cost in this scenario - tidal still costly relative to mature renewables.

Tidal economics improve at scale and with FIT/CFD support. Contract for Difference auctions have set tidal at 200/MWh - much higher than solar (40/MWh) or wind (40-70/MWh). With CFD support, tidal projects are viable but not yet competitive on pure market price. Technology improving; expect cost reduction over next decade.

A worked example

Try the defaults: install cost of 10,000,000, capacity of 1,000, capacity factor of 35%, electricity price per kwh of 0.15. The tool returns -68.02%. You can adjust any input and the result updates as you type — no submit button, no reload. That's the real power here: seeing how sensitive the output is to one or two assumptions.

What moves the number most

The result responds to Install Cost, Capacity (kW), Capacity Factor %, Electricity Price per kWh, and Maintenance % of Install Annual. Not every input has equal weight. Adjusting one input at a time toward extreme values shows which ones move the result most.

The formula behind this

Annual kWh = capacity × 8760 × CF. Revenue = kWh × price. Maintenance = install × %. Net = revenue - maintenance. Everything the calculator does is shown in the formula box below, so you can check the math against your own spreadsheet if you want.

Beyond the number

Carbon, health, and local air quality don't show up on the calculator but often drive the decision. The financial figure is a lower bound on the value; the rest is whatever you'd pay for the non-financial benefits.

What this doesn't capture

Carbon reduction, health benefits, and local air quality have real value the financial figure doesn't price. The calculation gives the money side honestly; for the full picture, note the non-financial benefits alongside.