SolarHacks

Inspiration

Many homeowners want to go solar but have no idea where to start. Generic calculators spit out rough numbers. Getting an actual quote means talking to a salesperson. And almost nobody knows about the federal tax credits and state rebates sitting on the table. We wanted to build the tool we wish existed, one that gives you the full picture in under 60 seconds, for free, with no sales pitch.

What it does

SolarHacks gives any U.S. homeowner a complete clean energy roadmap from a single address. It analyzes solar potential using real roof data, scores wind and geothermal feasibility, calculates carbon offset with EPA equivalencies, surfaces every IRA rebate and state incentive you qualify for based on income, and models 20-year savings across 1,000 Monte Carlo scenarios. It wraps everything up with a GPT-4o summary that tells you exactly which technology to prioritize and why for your specific home.

How we built it

Frontend: React 18 + Vite + Tailwind CSS + Recharts. We use the Google Maps JS API to render the user's actual roof with a live solar flux overlay (GeoTIFF rendered via canvas), and a panel count slider that updates estimates in real time. Backend: Python + FastAPI. When the user hits Analyze, the backend fires parallel requests to Google Solar, EIA, NREL Wind Toolkit, Open-Meteo (ERA5-Land reanalysis), and Rewiring America. A NumPy-based Monte Carlo engine runs 1,000 simulations randomizing utility inflation, panel degradation, cost overruns, and production variance to produce p10/p50/p90 savings ranges. OpenAI GPT-4o generates the plain-English summary from the aggregated results. Deployed on Vercel (frontend) + GCP (backend).

Challenges we ran into

The Google Solar GeoTIFF flux maps required custom canvas rendering and coordinate projection logic Wiring 7 different APIs with different response shapes into a single unified report object required careful parallel async design on the backend. Open-Meteo's archive API rate limits requests for large historical datasets, so we had to switch from different calls so our service always stays running.

Accomplishments that we're proud of

A real Monte Carlo simulation, not a single estimate, so users see an honest range of outcomes instead of a unrealstic number. End-to-end coverage of all three residential clean energy technologies (solar, wind, geothermal) in one tool. The income-based IRA incentives calculator that surfaces actual rebate amounts most homeowners don't know they qualify for. The app is fully deployed and works on any U.S. address right now.

What we learned

How the Google Solar API's building insights and data layers actually work under the hood, including GeoTIFF parsing and solar flux visualization. How to model financial uncertainty properly with Monte Carlo instead of point estimates. How ERA5-Land reanalysis data can proxy geothermal suitability without needing a physical site assessment.

What's next for SolarHacks

Contractor matching: connect users to vetted local installers after they see their report Shareable report links: let users send their analysis to family members or contractors Multi-year tracking: let homeowners log their actual bills and see real vs. projected savings over time

Built With

• eia
• fast-api
• gcp
• google
• google-maps
• nrel
• open-meteo
• openai
• python
• react
• recharts
• solar
• tailwind
• uvicorn
• wind