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Energy·validated

Solar PV

Why it matters

Photovoltaics have fallen in price faster than any other energy technology. What was an oligarch's toy twenty years ago now sits on ordinary village roofs, and the economics keep improving every year. Our World in Data turns that observation into a sourced curve: module prices have dropped roughly 90% in the last decade and over 99% since 1976, falling about 20% with every doubling of global installed capacity (Wright's Law). The drop has already carried panels to village-roof scale elsewhere. Bangladesh's solar-home-systems program reached around 20 million people through some 4 million small off-grid rooftop systems, the World Bank reports. A solar array is the quietest machine a building can own — no fuel, no combustion, no moving parts, no operating emissions, and no dependence on any grid, pipeline, or tanker. In Ukraine, blackouts turned energy from an invoice into a survival question. PV plus a battery became the difference between a dark house and a working one. And solar is the engine of every other fossil-free choice. A heat pump is only as clean as the electricity that feeds it, and a roof that makes its own closes that loop.

Role in 001's holistic picture

PV is the generation heart of the Energy Innovation Model. That heart feeds the battery, drives the heat pump, and defines the budget that Energy Management allocates. Its winter behaviour is a discipline of its own, Winter-Optimized PV. That is because the season when a building needs energy most is the season a textbook array delivers least. Ultimately, PV is the reason Building Autonomy stopped being a fantasy and became a sizing exercise.

How 001 engages with it

House 001 runs on a 6 kW array with measured results. Peak daily generation reaches 17–18 kWh, the house holds full energy independence from mid-February to mid-November, and summer surplus charges two electric vehicles. Beyond the house, the array fuels the household's transport. Stage 2 plans add 4–5 kW of panels. After a year of live-testing a wind turbine beside the house, the winter gap looks more and more like a question panels and storage will answer. At Tepla Gora, an off-grid PV system with battery storage was designed and installed on-site. It carries the community's daily loads.

For Unity Hub we took PV past where the textbooks stop. A winter-first design study covered vertical bifacial panels, snow albedo, and diffuse-light physics. It became its own publication and its own sense page. Among the findings is an honest one: oversizing the array to ~20-30 kW is one of the cheapest ways to survive a Carpathian December.

Maturity: validated. Measured through years of operation at House 001; running off-grid at Tepla Gora; winter-optimized design researched and published for Unity Hub.

Further reading