By Andres Gonzalez and Isla Binnie MADRID (Reuters) -British renewable power generator and network operator SSE has agreed to buy a portfolio of onshore wind development projects from Siemens Gamesa, the company said on Tuesday confirming a Reuters report. SSE Plc will pay 580 million euros ($626 million) for the wind farm projects, which have the capacity to generate 3.9 gigawatts (GW) of electricity in France, Greece, Italy and Spain. A team of up to 40 staff would be integrated into SSE as part of the agreement. The transaction includes an agreement for Siemens Gamesa Renewable Energy SA to…