Over time I have become convinced that, amongst a myriad of sources, the energy used to operate our buildings stands forth as perhaps the principal cause of climate change. This perspective has come to play a central role informing the work I do.
Below is a collection of some of the information which has informed this perspective.
This graph, from the DOE, gives an overall snapshot of where energy is used in the US.
In residences: heating.
In commercial buildings: lighting.
Here in the US, buildings are the largest source of CO2 emissions, by far.
Why can’t we just switch over to renewable energy? Because the gap between what slowly-growing renewable sources like solar and wind can make and what we use is far too large. This graph from the Passive House Institute US is based upon projections by Shell Oil. It illustrates one interested company’s projection of that gap. Even with expected growth, the renewable energy sources noted in green, blue, and yellow, fall far short of covering the shortfall in red: a shortfall which currently looks likely to be filled by natural gas extracted by fracking. As a professional with experience in the solar industry I am unable to share in the confident attitude that renewable technologies are advancing anywhere near fast enough to cover large-and-rapidly-growing global energy demand.
Another illustration of the same gap.
This image also illustrates that, in general, building energy use can be taken as very closely equivalent to CO2 emissions, because so little of our building’s energy sources are renewable.
This graph illustrates that the energy used – and by extension the CO2 emitted – come from operating buildings, not from building them. Even over a modest 50-year expected lifespan, the energy used to construct a building is dwarfed by what is needed to keep it warm, cool, illuminated and in good working order.
As individual human beings, we Americans are amongst the select group creating the very most CO2 emissions. This map shows per capita CO2 emissions by country, based on data gathered by the UN. Although this data is a couple years old and may not be perfect, the point seems clear enough: using our own highest measuring stick – individual responsibility – it is not the Chinese creating global warming, it is us.
This graph shows the well-publicized contemporary increase in global CO2 emissions with projected levels if increases continue at current rates.
I am not able to share in the confident attitude that climate change will be someone else’s problem, or that human societies as we know them will be readily able to absorb the kinds of transformations implied. This image shows the impact of sea rise on lower Manhattan, dwarfing the comparatively modest flooding which resulted from Hurricane Sandy. It represents billions or trillions of destroyed real estate, destroyed public transit and utilities, pollution and massive dislocation. This image does not begin to speak to larger conditions like crop growth patterns which keep human societies around the globe in stable relation to one another. Can we take such speculations so lightly?