Under the British administration, concessions from the Mandatory government were given. On 12 September 1921, the British formally signed the “Auja (or Yarkon) Concession” which granted Pinhas Rutenberg's Jaffa Electric Company a 70-year concession granting it exclusive rights to generate, distribute, and sell electricity in the administrative District of Jaffa, and authorized Rutenberg to generate electricity by means of hydroelectric turbines that would exploit the water power of the Auja (Yarkon) river. However, Mavromatis challenged the concession claiming that his concessions conflicted with the Auja Concession and that he was being deprived of his legal rights. The Mavromatis concessions, in effect despite earlier British attempts to abolish it, covered Jerusalem and other localities (e.g., Bethlehem) within a radius of around the Church of the Holy Sepulchre. In the end, Rutenberg's company concessions remained and the company built a power plant that produced electricity using diesel-fueled engines, and by 1923 Jaffa Electric Company's grid covered Jaffa, Tel Aviv, neighboring (mainly Jewish) settlements, and the British military installations in Sarafand.