From formulae and tabulated data for every geographic location in the program's database hourly adjusted temperatures throughout the 24 day are calculated. Naturally these can only ever be considered to be estimates as the same day of the year in two or more consecutive years are never likely to be identical, particularly in temperate climates that are more likely to experience frontal weather systems. Designing for 'worst case' conditions to determine peak loads is however far more accurate as local annual highest and annual lowest temperatures are usually quite well known and recorded. Hourly temperature profiling does however provide a useful model profile of likely or typical energy requirements.
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