There are many different methods for making coffee, some more energy-efficient than others. However, there are no coffee makers that you can power with a small solar PV panel. For example, a commercially available 12V DC drip coffee maker requires a solar panel of 300 watts to brew coffee and keep it warm.

The key to making a more energy-efficient coffee maker is insulation. Regardless of which conventional coffee maker you purchase, it will typically have little to no heat insulation, and most of the heat generated by the energy source will be wasted into the environment. Therefore, we made an insulated solar electric coffee maker ourselves.

Our coffee maker operates on the same principles as our solar-powered oven and runs on a 100W solar panel. We embedded an Italian coffee maker—a moka pot—in a mortar slab, surrounded by cork insulation and a layer of ceramic tiles.

The cooker has an electric resistance heating element integrated inside, which is directly connected to the solar panel without a battery, solar charge controller, or voltage regulator in between. Although it’s solar-powered, the coffee maker can be located inside your kitchen or next to your bed—only the solar panel needs to be outside.