The Sun is our energy superpower

In physics, one joule, the standard measure of energy, is roughly what you need to lift an apple up one meter against the force of gravity.

Power is how fast energy is produced or consumed. One watt, the standard measure of power, represents the use of one joule in a second. A megawatt is a million watts.

Canada could try to be an energy superpower, producing and consuming as much energy as possible, as quickly as possible. But why? This is like picking up the apple, putting it down, then picking it up again, over and over.

You only need to lift up the apple once to eat it. Far better is to practice energy sobriety. Use just enough energy to satisfy essential needs. Minimize waste.

Nature does this using energy from the Sun, our true energy superpower.

The power of the Sun, generated by nuclear fusion, is constant, at 386 billion billion megawatts. Not quite half a billionth of this falls on the Earth, about 173 billion megawatts.

Since Earth is a living planet, with an active water cycle, about 41 billion megawatts of solar power is used continuously to lift water into the atmosphere. Water is either evaporated from oceans and lakes (~ 90 per cent), or transpired through plant leaves (the other 10 per cent). Evapotranspiration absorbs heat and cools the Earth’s surface. The absorbed heat is released again when water vapour, a gas, condenses back to a liquid in the atmosphere. This forms clouds, which have a cooling effect and produce rain.

A good way to be an energy superpower is to increase transpiration by restoring vegetation cover. This creates a positive feedback—more plants, more transpiration, more local rainfall, more plant growth—the living climate. We need, urgently, to allow vegetation to cover as much land area as possible, enhancing this positive feedback.

Increased vegetation cover can counter a different and very destructive feedback loop happening right now: Wildfires emit carbon dioxide that traps heat in the atmosphere, causing hot and dry weather, leading to more severe and larger wildfires.

Plant growth has an additional energy superpower benefit: increased photosynthesis. Plants harvest light energy from the Sun and store it in their tissues as “biomass.” Most of this biomass is then eaten, or decays when plants pass away. Some biomass is stored as organic carbon in soils, removing carbon dioxide from the atmosphere.

More biomass means more and faster energy flow—more power. At present, photosynthesis captures roughly 110 million megawatts of solar energy globally. This exceeds the 15.8 million megawatts of fossil fuel energy that people consume constantly, but it can still be increased.

Canada wants to be an energy superpower but is going about it in the wrong way—building pipelines to increase the production and use of tar sands bitumen and liquified natural gas. Unfortunately, this releases greenhouse gases. Let’s scale back fossil fuel extraction, along with timber harvesting and other vegetation clearing activities. Allow ecosystems to mature, cycle more water, rehydrate the continent, and store more carbon.

Owing to the greenhouse effect, fossil carbon dioxide and methane are causing a massive ongoing imbalance in Earth’s energy budget: roughly 1,500 million megawatts. Some two thirds of this excess heat is radiated out to space, but 500 million megawatts are retained. About 90 per cent warms the oceans. The remaining 10 per cent warms and dries out the continents: depleting groundwater, causing forest fires, and melting glaciers.

This added heat far exceeds that which is directly released when fossil fuels are burned. It is many times greater than the energy captured through photosynthesis. Trapped heat does not contribute to energy superpower status. It cannot be used productively. It destabilizes the climate.

The wise path to energy superpower status is use of solar energy. There are many ways to do this: with more vegetation cover and photosynthesis, with solar panels that use the photovoltaic effect, with hydroelectric power enabled by solar-powered evapotranspiration, or with wind turbines powered by the differential solar heating of the Earth’s surface.

Also important is to keep in mind energy sobriety. Use only what is needed, leaving as much as possible for other people and other species.

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