In April, a group of 93 private investors who have invested a combined €5.8 million in Exergyn, a potentially ground-breaking clean-tech start-up, dispatched a letter to the company’s board and other interested parties expressing their dissatisfaction with the strategy being pursued by the company. It was a bold move, but it was based on a conviction of the company’s potential. All sides in the corporate tussle agreed however that the Irish company had made huge advances in its mission to solve one of the biggest challenges in reducing climate change: how to cool and heat things in a way that…