Energy-efficient houses: For Japan homebuilders zero is magic number

Energy-efficient houses: For Japan homebuilders zero is magic number

TOKYO — Major homebuilders in Japan are hoping to sell many more net-zero energy houses, that is, homes whose efficient designs and solar panels mean they have a net energy consumption of zero. In some cases, they may even be net energy producers.

      Misawa Homes plans to build zero-energy houses for sale on a large scale in fiscal 2017. The company has already introduced homes with high-performance fiberglass insulation and solar panels as standard features in relatively inexpensive houses targeting people in their 30s. 

      It sold 66 zero-energy houses in fiscal 2014, accounting for 1% of total new home orders. In response to growing interest from buyers, it has decided to focus on selling energy-efficient houses.

 Mostly zero

Panasonic unit PanaHome aims to make 85% of the houses it sells zero-energy houses by fiscal 2018, although in fiscal 2014 it sold almost none. The company says it costs around 70,000 yen ($580) a year to heat and power a zero-energy house, roughly one-fifth as much as it does for a house built 20 years ago. The money the homeowner makes selling electricity back to the grid from built-in solar panels should run to about 130,000 yen, leaving the owner with a net gain of 60,000 yen.

      In total, Japan’s 10 major homebuilders sold between 10,000 and 20,000 zero-energy houses in fiscal 2014. That number is expected to rise to more than 50,000 by fiscal 2020. A standard zero-energy house can save the equivalent of 1,200 liters of crude oil annually. Houses, which have seen slower gains in energy efficiency than factories and offices, are expected to begin closing the gap.

     Other leading homebuilders are jumping on the energy-efficiency bandwagon. Sekisui House hopes 70% of all the houses it sells will be zero-energy houses by fiscal 2016. Sekisui Chemical, which sells houses under the Sekisui Heim brand, wants to raise the share to over 50% of new orders by fiscal 2020.

(Nikkei)

Energy-efficient houses: For Japan homebuilders zero is magic number