The bill arrived and I assumed a meter fault. It wasn’t a meter fault. It was August, and it was me, running a modern inverter unit the way you’d run a 1990s one.

So I spent a month testing things, with a cheap plug meter on the indoor unit and a note on the fridge. Here’s what moved the number and what didn’t.

Switching it off when I left the room was the expensive habit

This is the one that surprised me. An inverter compressor is designed to run continuously at low speed once the room is at temperature, and low speed draws very little. Every time I killed it and came back an hour later, the unit had to pull the room back down from scratch, which means running the compressor flat out. Flat out is where the consumption lives.

Researchers have demonstrated a working quantum battery prototype that uses quantum mechanical effects to charge faster and more efficiently than conventional batteries at small scales. The results, published this week, show that quantum entanglement and superposition can be practically harnessed in an energy storage context — something that has been theorized for years but not convincingly demonstrated.

The “sort of” caveat: the prototype operates under highly controlled laboratory conditions and at scales far removed from anything you’d put in a phone or a car. The gap between proof-of-concept and consumer product is wide and filled with engineering problems that quantum elegance doesn’t automatically solve.

Mexico’s decision to supply oil to Cuba, openly stepping outside the boundaries of the long-standing U.S. embargo, marks a subtle but meaningful shift in hemispheric geopolitics. It is not a dramatic rupture, not a headline-grabbing confrontation—but that’s precisely what makes it significant. This is how policy frameworks erode in practice: gradually, deliberately, and with just enough ambiguity to avoid immediate escalation.

At the center of this move is a convergence of necessity and opportunity. Cuba is facing a persistent energy crisis, with fuel shortages translating directly into rolling blackouts and economic stagnation. Mexico, meanwhile, sits on a stream of heavy crude that does not always find optimal pricing in global markets. Cuba’s refining infrastructure is uniquely suited to process that grade of oil, creating a logistical alignment that is almost too convenient to ignore. What emerges is a transaction that can be justified both as humanitarian assistance and as commercially rational trade.

Nuclear power was supposed to be a fading technology. Expensive, politically toxic after Fukushima, outcompeted by renewables. The reversal now underway is genuine and worth understanding.

The driver is AI. Data centers powering large language models and the infrastructure they require consume enormous and rapidly growing amounts of electricity. Unlike residential or commercial demand, these loads are constant — 24 hours a day, 365 days a year. Solar generates during the day. Wind generates when the wind blows. Nuclear generates all the time, regardless of conditions. For a tech industry trying to guarantee power availability at scale, nuclear has become newly attractive precisely because of the attribute that made it economically awkward in a grid context: it does not stop.