The one-tailed \(P\)-value is \(0.0635\), suggesting only slight evidence supporting \(H_1\). To write a conclusion, an answer to the RQ is needed, plus evidence leading to that conclusion; and some summary statistics, including a CI (indicating the precision of the statistic):
Slight evidence exists in the sample (paired \(t=1.68\); one-tailed \(P=0.0635\)) of a mean energy saving in the population (mean saving: 0.54 MWh; \(n=10\); 95% CI from \(-0.19\) to \(1.27\) MWh) after adding the insulation.
The wording implies the direction of the differences (by talking of ‘savings’). Of course, statistically validity shoud be checked; this was done in Sect. 23.9, but the validity conditions are given again in the next section, for completeness.