Costs Low-costs 20 Performance 8 Cost benefit analysis 6 Cost effectiveness 6 Economic analysis 6 Wireless sensor networks 6 Commerce 5 Energy utilization 5 Internet of things 5 Wi-Fi 5 Wind power 5 Adhesives 4 Carbon dioxide 4 Controllers 4 Global warming 4 Investments 4 Natural gas 4 Renewable energy source 4 Simple++ 4 Solar cells 4 Application programs 3 Cameras 3 Cyclic voltammetry 3 Data acquisition 3 Design and tests 3 Digital storage 3 Electric inverters 3 Energy 3 Energy efficiency 3