* Clearing volume of 160,000 MWh recorded in first 100 days

* Total of 12 brokers participating now after 8 at launch

* European utilities seen entering market

FRANKFURT, Aug 24 (Reuters) - The European Energy Exchange (EEX) said its new clearing service for Japanese power futures, launched in May, was attracting strong customer demand and four more brokerages have joined the platform, bringing the total to 12.

More foreign energy companies and banks are seeking access to the Japanese power market, which was opened up to greater competition in the wake of the Fukushima nuclear disaster in 2011, spurring trading activity by generators, consumers, and distributors.

"Our launch is probably the kick-start for many organisations to speed up their entry into the Japanese market which is developing very fast," said Steffen Riediger, director Power Derivatives at the EEX in Germany, where it is headquartered, said in an interview with Reuters.

More than 160,000 megawatt hours (MWh) had traded over the first 100 days, equivalent to the annual power supply of 40,000 households, he said.

In Japan, utilities used to supply customers through bilateral deals but that changed when the market was opened up along with the roll-out of more renewables.

The deregulation has created more price volatility, making futures contracts more important for risk management as the Japanese market takes a similar course to that seen in Germany 20 years ago.

The EEX products comprise the clearing of trades for weekly, monthly, quarterly, seasonal and annual power delivery up to six years in advance.

Brokers Nissan Securities, GFI, Ginga and Tradition Singapore have become partners, adding to eight companies present at the launch, Riediger said.

EEX, a subsidiary of Deutsche Boerse, aims to bring more Asian markets to its global online platforms.

The trading arm of German utility RWE's said last month it was setting up an office in Tokyo, which will start local power trading in the autumn.

Other European utilities are also looking to hire in Japan, Riediger said. (Reporting by Vera Eckert, editing by Jane Merriman)