Sempra and RBS have agreed a joint venture to create a trading arm for European commodities. It was always suprising that RBS did not do this themselves given how much debt and equity they have invested in European power assets, but they always felt that the need to trade does not always go hand in hand with the financing of assets. Arguably as long as they have a handle on what prices are doing then financing is far more complex.

Sempra on the other hand seemed to have disposed of assets and set themselves up purely as financial traders, good if the trading is going well but not so good when the markets go against positions you shouldn't have. Sempra have had some quite high profile mistakes, most notably the purchase of Atlantic energy, after they owed them £10m+ and went into receivership.

It looks like a good marriage as both will benefit, but how long will it last. History suggests that eventually divorce will happen look at Louis Dreyfus and EdF.