With solar power, the biggest leaps in technology are coming with battery storage.

Currently most homes with solar systems can only use power from their roofs when the sun is shining. Batteries mean they can store that energy for use at night.

The Tesla Powerwall home battery for example aims to revolutionise the way solar power users consume energy.

The batteries use lithium-ion batteries and the same technology as Tesla vehicles, rather than traditional lead-acid batteries.

Enphase and Samsung are also developing better battery technology.

The other revolutionary battery making its way into New Zealand is the Aquion Energy saltwater battery, which distributor Taspac claims is the world's first environmentally friendly battery...