Perform calcs as below to find your loads. Dropping sensible load to 65 will lower your humidity which may require humidification. It depends on how you want to operate. Bottom line, the more energy you use to condition your space, the more expensive your costs. The upside to keeping your space at 65 is you have created a heatsink during cooling failure. May only be 30 minutes or so, but may be enough time to correct a minor problem.

Below taken and edited from RSES SAM Manual..... (www.rses.org)

Is = Np x Fs + Lw x 3.41 + Lf x 4.25 + NM x HP x 3393 + As

where:

Is=sensible internal heat gain, Btu/hr

Np=number of occupants

Fs=occupancy heat gain, sensible, Btu/hr

Lw=electric lights, incandescent, watts

LF=electric lights, fluorescent, watts

NM = number of electric motors

HP = motor HP

As=appliance heat, sensible, Btu/hr


IL=NP×FL+AL

where:

IL=latent internal heat gain, Btu/hr

FL=occupancy heat gain, latent, Btu/hr

AL=appliance heat gain, latent, Btu/hr

Use actual or assume a fluorescent lighting load of 1.5watts per sq ft of floor space.

Use actual or assume (For FS and FL) 250 and 200 Btu/hr per person respectively.