Table 3.

Sensitivity analysis for a variation in energy demands.

Variation	−20%	−10%	0%	+10%	+20%
System composition
Gas engines	2	2	3	3	3
Hot water boilers	3	3	3	3	4
Heat exchangers	3	3	4	4	4
Absorption chillers	1	1	1	1	1
Mechanical chillers	2	3	3	3	4
Cooling towers	3	3	3	4	4
Natural gas (total) MWh/yr	25,896	26,349	37,324	38,301	38,689
Purchased electricity MWh/yr	0	9	29	0	0
Sold electricity MWh/yr	7340	6981	11,389	11,269	10,905
Natural gas (cogeneration) MWh/yr	24,896	24,831	36,638	37,246	37,189
Cogenerated electricity MWh/yr	10,162	10,135	14,954	15,202	15,179
Cogenerated useful heat MWh/yr	6598	6981	8602	9161	9609
Primary energy savings %	12.65	13.99	10.01	11.00	12.08
Equivalent electrical efficiency %	57.85	59.36	55.22	56.17	57.25
Annual fixed cost €/yr	369,035	409,285	510,830	516,580	563,730
Cost of natural gas €/yr	647,391	658,718	933,092	957,513	967,215
Cost of electricity €/yr	0	1076	3207	0	0
Profit with the sale of electricity €/yr	−565,160	−537,535	−876,960	−867,692	−839,669
Annual total cost €/yr	451,266	531,544	570,169	606,401	691,275