Directly coupling DC power sources with DC loads can result in a significantly cheaper and more sustainable solar system.
Hydraulic power transmission is very efficient compared to electricity when it is used to operate powerful but infrequently used machines.
From the sixteenth to the twentieth century, urban farmers grew Mediterranean fruits and vegetables as far north as England and the Netherlands, using only renewable energy.
Contrary to its fully glazed counterpart, a passive solar greenhouse is designed to retain as much warmth as possible.
If we want the internet to keep working in circumstances where access to energy is more limited, we can learn important lessons from alternative network technologies.
These days, so many households have a WiFi-router installed that sharing the signal of these devices could provide free mobile internet access across densely populated cities.
The energy use of the internet can only stop growing when energy sources run out, unless we impose self-chosen limits.
Energy storage is often ignored when scientists investigate the sustainability of PV systems.
Almost all solar PV panels are now produced in China, where the electric grid is about twice as carbon-intensive and about 50% less energy efficient than in Europe.
If we are looking for quick and substantial energy savings for existing buildings, then local heating systems deserve our closest attention
Radiant and conductive heating systems make energy use independent of the size of a room or building.
Most modern heating systems are primarily based on the heating of air. This seems an obvious choice, but there are far worthier alternatives.