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Micro Wind

Electricity Generation

With capacity of 100 kilowatts or less, micro wind turbines are often used to pump water, charge batteries, and provide electrification in rural locations.

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Rank and results by 2050 #76

Micro Wind

Net cost (Billions US$): $36.12
Net operational savings: $19.90 billion
What do these numbers mean?

TOTAL CO2-EQ REDUCTION (GT)

Total CO2-equivalent reduction in atmospheric greenhouse gases by 2050 (gigatons)

NET COST (billions US $)

Net cost to implement

SAVINGS (billions US $)

Net savings by 2050

Impact:

Increase micro wind fivefold to 1 percent of global electricity generation by 2050, and it can deliver .2 gigatons of emissions reductions. Like in-stream hydro, micro wind turbines allow for the extension of clean, renewable electricity in areas without grid access.

Micro Wind

Electricity Generation

With capacity of 100 kilowatts or less, micro wind turbines are often used to pump water, charge batteries, and provide electrification in rural locations.

With capacity of 100 kilowatts or less, micro wind turbines are akin to the windmills of yore—standing solo in a cornfield, capturing the wind’s kinetic energy to meet the electricity needs of a family or small farm. Today, they are often used to pump water, charge batteries, and provide electrification in rural locations, all without producing greenhouse gases.

Experts estimate that a million or more micro wind turbines are currently in use around the world. The key factor for growing that number is cost. Currently, the price per kilowatt of small-scale wind is much higher than that of utility-scale turbines, and payback periods can be long, in part because they are installed individually.

In lower-income countries, micro wind turbines can help expand access to electricity, giving people a way to light their homes or cook their evening meals, which can avoid emissions from dirty diesel generators or kerosene lamps.

Micro turbines can also be placed on large structures, such as skyscrapers, to take advantage of stronger, steadier breezes. The Eiffel Tower now sports vertical axis turbines that produce electricity for use on site.

Vs

Composting

Food

From backyard bins to industrial-scale operations, composting food waste converts organic material into stable soil carbon and valuable fertilizer, averting methane emissions.

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Rank and results by 2050 #60

Composting

Reduced CO2: 2 gigatons
Net cost (Billions US$): $-63.72
Net operational savings: $-60.82 billion
What do these numbers mean?

TOTAL CO2-EQ REDUCTION (GT)

Total CO2-equivalent reduction in atmospheric greenhouse gases by 2050 (gigatons)

NET COST (billions US $)

Net cost to implement

SAVINGS (billions US $)

Net savings by 2050

Impact:

In 2015, an estimated 38 percent of food waste was composted in the United States; 57 percent was composted in the European Union. If all lower-income countries reached the U.S. rate and all higher-income countries achieved the E.U. rate, composting could avoid methane emissions from landfills equivalent to 2.3 gigatons of carbon dioxide by 2050. That total excludes additional gains from applying compost to soil. Compost facilities cost less to construct but more to operate, which is reflected in the financial results.

Composting

Food

From backyard bins to industrial-scale operations, composting food waste converts organic material into stable soil carbon and valuable fertilizer, averting methane emissions.

Nearly half of the solid waste produced globally is organic or biodegradable. Much of it ends up in landfills; there, it decomposes in the absence of oxygen and produces the greenhouse gas methane, which is up to 34 times more powerful than carbon dioxide over a century. While many landfills have some form of methane management, it is far more effective to divert organic waste to composting.

Composting ranges in scale from backyard bins to industrial operations. The basic process is the same: ensuring sufficient moisture, air, and heat for soil microbes (bacteria, protozoa, and fungi) to feast on organic material. Rather than generating methane, the composting process converts organic material into stable soil carbon, while retaining water and nutrients of the original waste matter. The result is carbon sequestration as well as production of a valuable fertilizer.

Human beings have long used compost to feed gardens and fields. Today, it is especially useful for managing growing urban waste streams. In 2009, San Francisco passed an ordinance that makes composting the city’s food waste mandatory. Copenhagen, Denmark, has not sent organic waste to landfill in more than twenty-five years, reaping compost’s win-win-win of cost savings, fertilizer production, and reduced emissions.

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