The thesis

A clean grid runs on what it can store.

The world is adding renewable generation faster than it can store it. Increasingly, the value of clean energy is decided not by how cheaply we make it, but by the batteries that hold it until demand arrives. This publication is about those batteries.

Solar and wind produce power when the sun shines and the wind blows, which is rarely when a city actually needs it most. That mismatch, between when clean energy is generated and when it is used, is the central engineering problem of the transition. Solve storage and renewables become dispatchable. Fail to, and we keep burning gas to cover the gaps.

Most of today's storage is built on lithium ion, the same chemistry that powers phones and electric cars. That is not obviously the right choice. A battery that is ideal for a vehicle, where weight and size dominate, has very different priorities from one bolted to a grid, where it never moves and may run daily for fifteen years. We think the most interesting work in energy storage is happening where people stop assuming the car battery is the answer.

What we cover

Two questions, mostly. First, the chemistry: what an aqueous zinc-ion cell actually is, and why a water-based, non-flammable battery is compelling for storage installed around people. Second, the trade-offs: a clear-eyed comparison of zinc-ion and lithium-ion that resists the urge to crown a single winner, because the right chemistry depends entirely on the job.

Latest writing

The case for storing heat instead of electricity A hot water tank is a battery for heat loads, with no round-trip conversion losses. That matters more than grid planners typically acknowledge. When the wind doesn't blow for a week The four-hour battery solves the evening peak. The multi-day calm is a different problem, and the technologies competing to solve it look nothing like lithium-ion. In praise of boring batteries The battery that will decarbonize the grid is unlikely to be the exciting one. For storage that never moves, cheap, safe, and durable beats dense and clever almost every time. The grid's hardest hour is after sunset Why the defining challenge of a renewable grid is not making clean power but covering the few hours each evening when the sun is gone and demand is not.

All writing →

A note on where we sit

Salient Energy is produced from the Region of Waterloo in Canada, a corner of the country with a deep bench in advanced materials and a long line of cleantech companies, among them the zinc-battery developer this domain once belonged to. We are an editorial project, not a manufacturer. The interest is in the field, not in selling you a cell.