Solar 12

Lore & Background

On the desolate, rust-streaked world the player has colonised, sunlight is the one resource that never runs out—provided the factory is built where the sky is clear. The original 1×1 panel, unlocked by Solar 1, was a proof-of-concept: a single dark cell latched to a concrete pad, sputtering enough juice to light a few lamps. Solar 12 scales that idea into something an engineer can actually plan around. The 2×2 panel is a quad-cell array, its photovoltaic surface a deep indigo that glows faintly as the in-game sun tracks overhead. In the broader narrative of the player's industrial conquest, the solar tier is where the factory begins to look less like a desperate survival camp and more like a civilisation. Where coal generators belch smoke and demand constant fuel logistics, a field of 2×2 panels simply sits there, patient and silent, converting starlight into megawatts. The alien flora—those strange blue-green plants that dot the terrain—seem to thrive in the long shadows the panels cast, as if the world itself is slowly adapting to the new geometry of the settlement. By the time a player has laid down a few hundred of these panels in a neat grid, the factory has a rhythm that matches the planet's day cycle: a slow swell of output at dawn, a plateau at midday, a gentle taper at dusk. It is, in many ways, the most *Factorio* moment in the game—the feeling that you have built something that works in harmony with the world rather than merely extracting from it.

In Their Own Story

The sun was low and amber, dragging long shadows across the concrete. Kestrel crouched beside the new 2×2 array, her boots dusty, and watched the cells drink the last light. Around her, a hundred and thirty-two panels stretched to the tree line, each one a small dark square in the rust-coloured dirt. No smoke. No rumble of the coal generator. Just the faint hum of the battery bank absorbing the evening charge. She pulled up the blueprint on her tablet—the one she'd saved three days ago, when the old 1×1 grid had finally maxed out and the factory had started stuttering. She'd typed the coordinates, hit save, and walked away. Now she was walking back, and the grid was bigger, and the factory was breathing easier. Somewhere past the tree line, the alien plants swayed in a wind that smelled of iron and ozone. Kestrel straightened up, brushed the dust off her knees, and started laying the third row.

Reader's Guide

Solar 12 is found in the Energy tab of the research screen. It unlocks the Solar Panel 2, a 2×2 photovoltaic array that produces roughly four times the energy of the 1×1 panel while occupying the same total footprint (four tiles). This makes it the first solar tier where area efficiency becomes a real design consideration. Prerequisite chain: Solar 1 → Solar 12 → Solar 3 → Solar 4. You must complete Solar 1 before researching Solar 12. In practice, players also need a working battery system and at least one electric furnace or electric engine to put the extra power to use, so Solar 12 typically lands in the early-to-mid game, after basic logistics and the first tier of electric machines are online. Research cost is modest by mid-game standards, placing it well before the heavy science-pack sinks of late-game techs. It does not require any rare science pack tier, keeping it accessible to players who are still building their first assembler line. In the broader tech tree, Solar 12 sits alongside other energy technologies like Battery, Electric Furnace, and Electric Engine. The natural build order is to research Solar 1, get a handful of 1×1 panels running, then immediately queue Solar 12 so you can swap to the larger panels before your power demand outpaces the small grid. Once Solar 12 is done, most players strip out the 1×1 panels and rebuild the array with 2×2 units, reclaiming land and simplifying the layout. Blueprint interaction: because solar panels are placed as regular entities, you can blueprint an entire solar farm, save it, and paste it elsewhere. This is especially useful when expanding to a second base or when you want to replicate a proven layout. The blueprint does not carry research state—your friend still needs Solar 12 in their own tech tree before the 2×2 panels will function.

Did You Know?

• Solar panels in Factorio produce no energy at all during the in-game night phase, making battery storage or a secondary fuel source essential for 24/7 operation.
• The 2×2 Solar Panel 2 occupies exactly four tiles, the same total area as four 1×1 panels, but the larger single entity is easier to blueprint, remove, and reposition as a unit.
• Because solar output scales with the sun's position, players often orient their solar farms to maximise exposure during the longest daylight stretch of the game's day cycle.
• Solar panel technologies form a strict linear chain (1 → 12 → 3 → 4), so you cannot skip a tier—each larger panel requires the previous one to be researched first.