Weather & Energy In Buildings

People and animals shelter from weather.

Energy is used to maintain comfort, either body heat and insulation act alone  in a "passive" building or the building is "active". Ever since humans first gathered wood to keep warm, energy efficiency has been an issue, in buildings. Who wants to spend their whole life cutting down trees? The word energy even means activity .

So "Building Energy Intelligence" is all about doing less by being more efficient.  Think of it as a sophisticated laziness - pretty much all technologies are about doing less to get more out of the effort and construction technology comes up in the very first paragraph of the Wiki link above. This implies a large amount of human effort goes in to doing less !

So it is quite a surprise that for the most part of the 20th century nobody gave tuppence (insert thing of little value here) for energy costs, and it is no surprise that it is becoming a bit of an issue.

This blog tries to explain how energy use in buildings can be understood.   Generally it is common sense but it's not all that easy...

This little chart shows how daily heating energy consumption falls as average outside temperature rises:

The graph was drawn automatically from Smart-meter data by kWIQly

  • Winter is on the left and summer on the right.
  • The height of the bars represent average rates of fuel consumption.
  • The main thing to notice is that the profile is not a straight line.
At the high end of consumption (in winter) this building is at the limit of its' heating capacity - The temperature where this happens is interesting if the building gets cold in very cold weather. It suggests that there is a "design limit" to the building in effect.

At the low end of consumption (as we head towards summer) at some point effectively no more heat is required.  This means the weather is above the "balance temperature" of the building. Any consumption above this level heats a building which is warm enough causing waste by driving cooling or more often simply discomfort.

A large part of the science of keeping buildings efficient depends on where and under what conditions these two transitions occur.Related articles
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