Uncharted Territories -- Part 2...
Philip Costa
One of the fossil fuels that we’ve been consuming faster and faster is methane—CH4. Today, we pull it mostly from the ground in the form of natural gas.
Gas means mostly methane here
But we could do like plants and build this carbon-based molecule by extracting carbon from the air, using the energy from the Sun.
The only difference is that plants produce sugar, and this machine would produce methane³.
Notice this: The only elements you need to produce methane are CO2 from the air and water! The only expensive thing you need is energy.
This becomes a question of energy cost: How can it be cheaper to generate CH4 from the air than by pumping it from the ground?
It’s a matter of time.
Over the long term, the cost of natural gas can only go up, because it becomes scarcer and scarcer, driving prices up. Also, companies must dig deeper and deeper to find it and pump it, which increases costs, and hence prices.
Meanwhile, the cost of solar energy is only going down.
It’s reducing so quickly that you need a logarithmic version of the graph to know what’s going on:
For the last 45 years, photovoltaic costs have been dropping by 12% per year!⁴ You could use the dropping cost of photovoltaic energy to generate the methane.
Important sidenote: It’s not time that reduces solar panel costs, but scale. The more we build them, the better we learn how to improve their efficiency.
But since our volume of solar panels has been growing exponentially over time, we end up with a consistent reduction in solar panel costs over time.
If pulling CH4 from the ground is only getting more expensive, and the energy needed to pull it from the air is only getting cheaper, at some point it becomes cheaper to pull it from the air than from the ground. The question becomes: How low does the cost of solar photovoltaic energy need to drop for this to happen?
To answer that, we need to understand how much energy is needed to produce methane. And for that, we need to understand the process to create methane.