How to save the planet

How to save the planet

Bill Gates wrote a book called How to Avoid Climate Catastrophe. Anyone concerned about the climate crisis will find it fascinating.

He begins by saying that there are two numbers we need to know:

(a) We currently emit around 51 billion tonnes of greenhouse gases each year. Each ton of these gases makes the Earth a little warmer.

(b) Our goal is to add zero greenhouse gases (“net zero”) to the atmosphere.

“Net zero” needs some explanation. No matter how hard we try, we will not be able to reduce greenhouse gas emissions to zero. We can reduce some emissions, for example by generating electricity without burning fossil fuels, using non-fossil electricity to power cars, homes and factories.

However, growing food crops with chemical fertilizers produces carbon emissions, and we will never stop doing it. Carbon emissions that we cannot avoid will need to be removed from the atmosphere so that our net emission is zero.

Gates explains that the following human activities all contribute to emissions:

Crafting things (specifically making steel and cement) contributes 31%

Electrical energy contributes 27%

Food culture contributes 19%

Transportation contributes 16%

Heating, cooling and refrigeration contribute 7%.

Gates uses the concept of green bonuses. Many human activities produce emissions, but in many cases the same activity can be performed without producing emissions; however, there is almost always a “green premium” or increased cost associated with avoiding emissions. For instance:

“The average retail price of a gallon of jet fuel in the United States over the past few years has been $2.22. Advanced jet biofuels, when available, cost an average of $5.35 per gallon. The green premium for zero carbon fuel is therefore the difference between these two prices, or $3.13. This is a premium of more than 140%. (Page 59)

In some cases, emissions from an activity (such as cement manufacturing) cannot be avoided with current technology; in this case, the “green premium” is the additional cost of removing emissions from the atmosphere (during the manufacture of cement). Emission suppression (direct air capture, DAC) currently costs about $200 per ton of CO2.

Gates mentions that although electric power accounts for only 27% of emissions, generating emissions-free electricity is the most important part of the solution, as many emissions from cars, factories and homes can be eliminated if they are powered by non-fossil electricity. .

Some things have a very low green premium. In this case, policy changes are needed. If a particular company makes a product in a way that avoids emissions (requiring it to spend a small green premium), the policy should prevent that company from being undermined by competitors that still produce emissions. The most effective way to achieve this is to put a price on carbon emissions, which can be done by taxing carbon emissions.

Some things have a very high green premium. In such cases, research is needed to determine how to reduce the green premium. Green premiums must become low enough for businesses in middle-income countries to go green; it will not be enough if only rich countries go green.

Gates discusses the difficulty of producing continuous electrical power with zero emissions. During the day, solar power only costs about 5 cents per kWh. However, if this electrical energy is stored in a battery and used at night, it will cost upwards of 15 cents per kWh. It is too expensive compared to electricity generated from fossil fuels; that’s why utilities that own solar power assets typically use gas-fired power plants for backup power. However, the combustion of the gas produces emissions.

Gates argues that at present, nuclear energy is the only non-fossil continuous energy that can be increased. Solar and wind power are intermittent and dependent on backing up fossil fuels; hydroelectric power is continuous, but requires sacrificing too much land. He mentions that he has invested in a company that is working on a next-generation nuclear power plant with energy storage. Nuclear energy can be stored as heat; at night, the stored heat can generate zero-emission backup power when solar power is not available.

Gates acknowledges that Chernobyl and Fukushima were serious accidents, but argues that we should have responded to those accidents by building better (safer) nuclear power plants, rather than abandoning nuclear power. Electricity demand will grow very rapidly in low-income countries as more people buy refrigerators, air conditioners and vehicles (remember, we want them to buy electric vehicles); so we need to make zero-emission electric power affordable.

Gates explains how making things (31% of total emissions today) can be done without any emissions. He points out that in some manufacturing processes, fossil energy can be replaced by carbon-free electricity. However, no one has figured out how to make steel or cement emission-free, because the chemical reactions that produce them produce CO2.

To make zero-emission cement and steel, carbon emissions from the process must be captured, resulting in high green premiums: 16-29% for steel and 75-140% for cement. In poor, urbanizing countries, the demand for steel and cement will be enormous; we need to find a way to reduce the green premium for these products.

Gates explains how growing food (19% of total emissions today) can be done with fewer emissions. Much of the emissions come from raising animals for meat and dairy. These emissions are likely to increase rapidly as people in low-income countries experience rising incomes and eat meat more frequently. Beef is particularly problematic because cattle consume 6 calories of feed to produce 1 calorie of beef.

He mentions that the best option is to develop plant-based meat substitutes that taste like the real thing and are cheaper than the real thing (i.e. with a negative green premium). This is going to take some research. The goal is to reduce global demand for animal meat and create demand for plant-based meat substitutes.

About half of the nitrogen in chemical fertilizers is not taken up by plants and eventually becomes nitrous oxide, a greenhouse gas. Unfortunately, feeding the planet is not possible without chemical fertilizers. Research is needed to find alternatives to current chemical fertilizers that produce fewer emissions; obviously, the demand for food will only increase with the growth of population and income.

Some have proposed planting trees on a large scale to absorb carbon emissions, but Gates explains why that simply won’t work. Our emissions are so vast that 24 million square miles (about half the world’s landmass) would need to be planted with trees just to absorb the lifetime emissions of the current population of the United States.

Gates explains how transport (16% of total emissions today) can be achieved with reduced emissions. Private cars and city buses are easy; the green premium of an electric car is low. However, electric cars are only zero emissions if the electric power is zero emissions. The problem is long-distance transportation: trucks that burn diesel, ships that burn bunker fuel, and airplanes that burn jet fuel.

All three need a large amount of energy for a long journey; a battery to store that much energy would make the vehicle too heavy (reducing its load or passenger capacity). We will therefore not be able to power these transports with batteries. Advanced biofuels can substitute for these fuels. These have high green premiums: 103% to replace diesel, 141% to replace jet fuel and 326% to replace bunker fuel.

Gates explains how heating and cooling (9% of emissions) can be done with less emissions. Fortunately, it’s simpler; much of the air conditioning is already electric and can become zero emissions by switching to zero emission electric power. At present, heating depends mainly on the combustion of fossil fuels. However, heating with an electric heat pump (like the heat pump that cools a refrigerator) is often cheaper than burning fossil fuels to heat a building (a negative green premium). This will change quickly if building owners can be incentivized to retrofit their buildings; it’s just a policy change.

Gates strongly argues that good government policies are essential. The most important step is simply to put a price (i.e. a tax) on carbon emissions. The fair price of emissions will make many green premiums negative. This will motivate every person and every company to reduce their emissions.

Funding for research aimed at reducing green premiums is essential. However, good policies will only be passed by elected officials if the public demands them. So the most important thing every person can do to avert climate catastrophe is to get involved in their community and demand the right policies.

Kazi Zahin Hasan is a businessman living in Dhaka.

#save #planet

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