Satellite Monitoring System for Remote Renewable Energy Systems in Brazil

摘要

A major part of autonomous renewable energy applications - such as PV - are electricity supplies in regions with no grid, no telephone coverage, and often with difficult accessibility. Commonly systems in such regions are supervised by yearly visits in conjunction with a data logger. Over the lifetime of a system the costs for supervision often significantly exceeds the cost of the system itself, e.g. for monitoring a system in the North-East Brazil: each yearly read-out of the data logger with travel expenses and personnel costs 600 EUD, so for 20 years of system lifetime this add up to 12,000 EUD. Response time for maintenance, repair and product improvements is poor. To overcome these disadvantages a data satellite transmission system using Brazilian satellites was set up in this project: It is compatible to the ARGOS protocol, facilitates very small transmitters (size of two matchboxes) and has a full coverage for whole Brazil and Latin America. Due to an agreement of our group with the ground control in Sao Jose dos Campos near Sao Paulo, the PV-Labs at UFRJ can monitor some systems for free. The disadvantage of the ARGOS system is the poor data transmission rate. The solution is data pre-processing and extracting the actual information needed to supervise a PV system in terms of yield, usage, and battery state. The relatively high initial costs for the transmitter (1,000 EUD) and the pre-processing unit (500 EUD) are already compensated after two years of usage by the saving of the travel and personnel expenses for the yearly supervision of the systems. The savings over the lifetime of a system are more than 10,000 EUD. The satellite data is transferred via ftp from the ground station in Sao Jose dos Campos to the Internet server of the PV-Labs at UFRJ in Rio, and is published from there worldwide via WWW. The advantages are manifold: The sponsors (NGOs, World Bank, national foundations, public etc.) have an immediate access to the projects ("Where did my money go?"), the manufacturers use the data to adapt their products to real operating conditions and, last but not least, the satellite online monitoring system provokes more public interest in the PV area.