Performance of a Pebble Bed Thermal Storage Integrated with Concentrating Parabolic Solar Collector for Cooking

Table 6

Comparison of efficiencies for the conditions of higher and lower DNI.

	DNI, highest	DNI, lowest
Solar energy on aperture area [MJ]	60.1	18.1
Stored energy [MJ]	40.1	12.85
Storage efficiency (%)	66.7	70.9
Volume of water boiled	5 liter for 53 min	5 liter for 4 h
Useful cooking energy [MJ]	1.47	1.47
Thermal efficiency of cooker (%)	45	31.1
Overall efficiency of cooker (%)	30	22.08