Bruno de Madrazo
Builds the calculators · compiles the data · edits every guide
I built Watt Guide because every "how much does X cost" page I found online answered with a vague range and an affiliate button. I wanted the actual math — the kind you can re-run with your own rate and your own house — so I wrote the calculators first and the guides second.
What I actually do here
I'm not an electrician, a solar installer, or an energy auditor, and I don't sell equipment — that independence is the whole point. What I do is concrete:
- Build the tools. The five calculators on this site — Solar ROI, heat pump vs gas, EV charging, whole-home payback and the electricity cost tool — are mine, end to end.
- Compile the data. Every cost figure traces back to a public dataset — EIA, NREL, DSIRE, Ofgem, ENERGY STAR, Eurostat — cross-checked across sources. If I can't source a number, it doesn't go in.
- Edit every guide. Drafts are researched with the help of AI tools, but every figure is fact-checked against the cited source and rewritten by me before it's published. The methodology page spells out exactly how.
Why "what does it actually cost me?"
Energy decisions — solar, a heat pump, an EV, even which fridge to buy — are sold with lifetime-savings numbers that assume best-case rates and inflation that never happens. The honest answer is almost always "it depends on your rate, your climate and your usage." So instead of guessing for you, the tools let you put in your own numbers. The guides exist to explain the assumptions behind them, and to say plainly when something doesn't pencil out.