One of the challenges of our modern society is to successfully reconcile growing energy demand, demographic and food pressure and ecological and environmental urgency. This book offers an update on a rapidly evolving subject, that of modern photovoltaic systems capable of combining the needs of energy and ecological transition. Although photovoltaic solar energy is a well-proven technical solution in terms of energy, its development can compete with agricultural land or natural sites. New solutions are emerging: the installation of photovoltaic parks on industrial wasteland; agrivoltaics, which reconcile agricultural activity and energy production on the same surface; and ecovoltaics, which make it possible to make use of the unused surfaces under solar panels by developing ecological solutions capable of providing services to nature. These innovations are part of the response to the need to preserve terrestrial and aquatic ecosystems, halt the decline in animal and plant biodiversity and participate in the development of a new mode of sustainable development and green economy.