Conservation Electric power 77 Energy conservation 25 Electric lighting 23 Energy consumption 20 Automatic control 19 Power supply 12 Design and construction 10 Electronic digital computers 10 Electric power transmission 8 Low voltage integrated circuits 8 Reliability 8 Arduino (Programmable controller) 6 Electric driving 6 Electric motors 6 Elephants 6 Energy dissipation 6 Equipment and supplies 6 Automobiles 5 Ecology 5 Dwellings 4 Embedded computer systems 4 Exhaust systems 4 Habitat 4 Lighting 4 Motors 4 Standards 4 Wildlife conservation 4 Birds 3 Electric equipment 3