How our housing can help keep carbon out of the atmosphere
By Rick Reynolds
There’s a whisper campaign among some climate scientists and industrialists involving a technology they say could pull us back from the brink. Dubbed “direct air capture,” it involves industrial plants that act like photosynthesizing plants in capturing CO2 from the atmosphere and returning it to the earth.
Their goal is to achieve “negative emissions” by reversing the levels of atmospheric carbon—rather than curbing it—to avert climate catastrophe. In effect, the plan would attempt to get the genie back in the bottle: the genie being the 40 trillion kg of carbon dispersed every year into the atmosphere by human activity—on top of the alarmingly elevated levels of atmospheric CO2 already existing.
This negative emissions strategy, which assumes that the atmosphere can be scrubbed like a dirty, deep-pile rug, is not practicable. Unless you happen to be photosynthesizing flora, it’s exponentially more efficient to capture carbon emissions at their source rather than after their dilution into the atmosphere. Beyond this, any inadvertent green-lighting of current (or greater) levels of CO2 emissions by promoting later capture, only encourages the problem one is trying to solve.
Belying the false promise of “direct air capture” is the fact that better strategies for mitigating climate change already exist. Powering high performance houses, transportation and industry through carbon-free electrical generation (solar, wind, hydro, tidal and nuclear) is likely the only viable way to reduce levels of CO2 in the atmosphere.
Short of immediate government regulation and industry buy-in on a global scale, which is hard to imagine, there is much we can do in the housing sector to cut emissions before they are emitted.
New single-family, multi-unit and mid-rise buildings could be built to passive house standards, with net-positive energy performance (creating more energy than they use) and constructed with carbon sequestering wood – all technologies that are available and in use today. Multi-unit housing promotes wiser land use, saves energy and eases congestion. Urban high-rise apartments, too, save energy and reduce the need for personal transportation.
Industry, including the construction industry, could run off carbon-free generation of electricity and use renewable/recyclable, carbon sequestering resources in manufacturing whenever possible.
But what about the cost of green electricity, you ask?
While advances in solar and wind technology are rapidly lowering the cost of electrical generation, they are necessarily limited by weather and nightfall. Short of vastly improved battery storage capacity, it’s likely the “when” of electrical usage will need to be regulated in the future, as “on demand” will prove too costly to the environment. The good news is: negative prices on electricity trading markets already exist.
According to a recent article in the New York Times, “Power Prices Go Negative in Germany, a Positive for Energy Users,” by Stanley Reed, some European consumers are paid to use power when surplus supply exceeds demand due to added renewable power generation. In such cases, periods of high wind and solar electrical production coinciding with low demand (and the inability of conventional power plants to efficiently scale back) can lead to electrical prices dipping below zero.
Major electricity consumers like factory owners in Germany, Belgium, Britain, France, the Netherlands and Switzerland have been paid the equivalent of $60 per megawatt-hour to take that surplus power off the grid. Better than free, they are actually paid to use the excess energy.
In the future, with more green energy feeding the grid (and battery storage capacity growing), regulating the intelligent timing of supply and demand cycles can clearly offset the cost of electricity. Augmenting carbon-free electrical generation, dead wood and plant matter would fuel government-regulated electrical generation–as well as being used as construction material.
As for all the existing, polluting stock (transportation, housing and industry), carbon capture (at the source) and green preserves would need to sequester atmospheric carbon until the major carbon culprits can be phased out through attrition and/or government mandate.
While these measures might seem draconian, they would still allow for many of the conveniences of the modern world. We’d still have comfortable housing and personal transportation. We could still bridge vast distances instantly on the internet, fostering our interconnectedness. And we’d be making progress on promoting a living planet and a livable future: arguably an excellent tradeoff.
Will humans come to these changes voluntarily? Will we bow to laws of atmospheric science before it’s too late? The answers may begin at home.*
*Building codes are catching up – 2015 building code calls for a maximum HERS score of 60 (we’re mostly in the 40-50 range, with max 3 ACH 50P (we’re at 0.06, but the code standard is almost 1/2 of what it was previously) – California code calls for all new homes to be net zero starting in 2020