RoofSolar
Financial-grade solar analysis for your roof — in 3 minutes
What it does
Most solar calculators give you a payback number with no working underneath. RoofSolar runs the actual 25-year cashflow for your address using live PVGIS irradiance data — IRR, payback, export-tariff earnings, battery economics, and EV savings — worldwide, no signup. Built by a project-finance modeler. Free; Pro PDF €3.99.
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- HWHelios – what plug-in solar could generate for any address in BritainMay 2026 · helios.southlondonscientific.com · ▲126
Plug-in solar panels (no electrician needed) have just become legal in the UK and will go on sale soon. Helios estimates how much electricity a typical installation could generate at a given address and what that's worth against your tariff. It uses UK government LIDAR data to reflect the actual skyline, so it knows whether there's a building or a hill blocking the sun. Caveats: - Outside LIDAR coverage (most of Scotland and Wales) it falls back to a synthetic horizon (less accurate). - Trees and recent developments (post-2022 or so) may not be in the data, and some address placements could…
AberSolarCalculator28d ago · abersolarcalculator.com · ▲2Solar calculator with roof direction & tax credit
My solar died for 6 months, so I built a watchdog27d ago · sunranker.com · ▲15Hi HN, Shawn here. My rooftop system lost about half a year of production and nobody told me. Not the installer, not the monitoring app, not the utility. I found out from an electric bill that made no sense, then spent weeks digging through the monitoring portal by hand. SunRanker is what I wished existed that day. Connect a system once (Enphase OAuth, or a SolarEdge site ID plus API key) and it reads production daily, shows it in plain language, and emails you when something actually changes. Three alerts only. The connection broke, the monitoring went quiet, or output has been well below…
More work this month
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Hey we are Computable. We spent years building trading infrastructure at Jump Trading and Coinbase. From that point of view, compute looks like energy markets before 2000: everything trades through private bilateral leases, there’s no visible price, and nothing can be resold. The same H100 rents at a 2x spread depending on who’s asking, and once you sign a 24-month lease, it can never change hands. So we built a market for GPU nodes, sold by the calendar week. Here are three things you can do on it that you can’t do anywhere else: - Buy exactly the weeks you need. Three nodes for the last…
Work · 11d ago · getcomputable.com
The app store for voice native apps that lives in your notch
Work · 29d ago · voiceos.com
Launched alongside, May 2026
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Parallel agents, diff reviewer, and multi-model comparisons
Dev tools · May 2026 · kilo.ai
- NW
Hey HN, Henry here from Cactus. We open-sourced Needle, a 26M parameter function-calling (tool use) model. It runs at 6000 tok/s prefill and 1200 tok/s decode on consumer devices. We were always frustrated by the little effort made towards building agentic models that run on budget phones, so we conducted investigations that led to an observation: agentic experiences are built upon tool calling, and massive models are overkill for it. Tool calling is fundamentally retrieval-and-assembly (match query to tool name, extract argument values, emit JSON), not reasoning. Cross-attention…
Life & fun · May 2026 · github.com
- FM
Dev tools · May 2026 · github.com