How do New York Times journalists use technology in their jobs and in their personal lives? Ivan Penn, who covers alternative energy for The Times from Los Angeles, discussed the tech he’s using.

Q. A lot of alternative energy is basically technology. What are some of the most unusual ideas around alternative energy you've seen break out over the years?

A. Much of the energy sector these days focuses on energy storage — that’s where a lot of innovation is taking place. Because solar and wind energy are intermittent, utilities look for ways to capture the unused power for when the sun doesn’t shine and the wind doesn’t blow. Lithium-ion batteries are commonly known, but engineers are also working on storing compressed air generated by using excess solar and wind and releasing it later to power a turbine.

The Los Angeles Department of Water and Power proposes to turn Hoover Dam into a giant battery by making it a hydro-pumped storage plant. The dam already generates electricity, but the utility wants to pump water back into the upper reservoir to produce more electricity using solar and wind electricity to power the pump — another form of storage.