There's no base 60 involved, it's the energy available divided by the power delivered:

178.8 Watt hours / 8300 Watts ≈ 0.0215 hours

Thanks, Not sure where my math went wrong.

	▲	NonHyloMorph 3 days ago \| parent [-]
		Hours to seconds conversion probably, the number 60 plays a role there. (Albeit not base 60 but mod 60, but I'm not firm enough in the math to rule out that there is some correspondence between the concepts)