Category: Energy

The current edition of Science focuses on energy and sustainability with a terrific online collection of notes, comments, and essays. Some notes from an article in this week’s edition of Science. The article is titled “Ethanol for a Sustainable Energy Future” by Jose Goldemberg. Some notes:

…exhaustible fossil fuels represent ~80% of the total world energy supply. At constant production and consumption, the presently known reserves of oil will last around 41 years, natural gas 64 years, and coal 155 years (2). Although very simplified, such an analysis illustrates why fossil fuels cannot be considered as the world’s main source of energy for more than one or two generations.

Today, ethanol production from sugarcane in [Brazil] is 16 billion liters (4.2 billion gallons) per year, requiring around 3 million hectares of land. The competition for land use between food and fuel has not been substantial: Sugarcane covers 10% of total cultivated land and 1% of total land available for agriculture in the country. Total sugarcane crop area (for sugar and ethanol) is 5.6 million hectares.

Subsidies for ethanol production are a thing of the past in Brazil (Fig. 2), because new ethanol plants benefit from the economies of scale and the modern technology available today, such as the use of high-pressure boilers that allow cogeneration of electricity, with surpluses sold to the electric power grid.

The current edition of Science focuses on energy and sustainability with a terrific online collection of notes, comments, and essays. Some notes from an article in this week’s edition of Science. The article is titled “Don't Forget Long-Term Fundamental Research in Energy” by George M. Whitesides and George W. Crabtree.

The energy problem is often phrased in terms of developing a strategy that roughly doubles the global production of energy by 2050 (from 13 to about 30 terawatts) . . .

Catalysis by design has periodically been embraced as a grand challenge, and periodically abandoned as too difficult, but nanoscience and surface science offer new approaches to this problem. The fundamental study of catalysis must be reanimated across the full spectrum of processes involved in energy and the environment…

We need new ideas, and we need to know which of the current smorgasbord of unexplored
and unproved ideas will work.
Developing affordable technologies for removing carbon from the atmosphere (for example, by growing biomass and converting it to a stable form of carbon) must be explored now, if they are to be options in the future. Changing the albedo of Earth, stimulating photosynthesis in the oceans by the addition of essential trace elements such as iron, developing new nuclear power cycles, a hydrogen economy, new methods for separating gases (such as CO2 from air) and liquids, room-temperature superconductivity to carry electric power without loss, biological H2 production, new concepts in batteries, and nuclear fusion—all must be explored fundamentally and realistically.