We need low-cost energy to advance civilization, allow the division of labor, and reduce the workload so that we have time to think, do our inner work, and build true civilization. Yet our energy solutions should not destroy the world we live in.
We must live on the incoming energy from the sun in one form or another. Until there are free energy devices which can tap aetheric energy directly, we are left with only a few choices: Solar cells, wind, water, and biomass (stored solar). Of course oil and gas are stored solar but they are not renewable. Also, the more refined the fuel, the greater our dependence upon the suppliers if we cannot refine it ourselves.
Wind and water (low-head hydro), are ideal if they are available, but they are not in most parts of the world. Solar cells are very expensive and vulnerable to catastrophic hail damage. So we are left with biomass which is suitable only for external combustion engines: steam and Stirling cycle. Steam is dangerous and requires close monitoring. So now we have only Stirling. Yet there are no practical low cost Stirling (hot air) engines available.
We are working on new Stirling energy devices that we hope will provide energy solutions for the future.