The Earth Story

Victoria Falls. Now that is some seriously powerful water.

Wind Power Grows

According to a new report by the Global Wind Energy Council the amount of wind energy generating capacity grew by 19% in 2012. The total amount of capacity is now at 282,000 megawatts (MW). We’ve seen that wind generated electricity is now on par with other sources when it comes to price (http://on.fb.me/13lQ8np) and its showing.

China and the US are leading the way with more than 13,000 MW of new generation capacity. Brazil leads South America with 1,077 MW of new capacity bringing them to 2500 MW, while Germany and the UK lead in Europe with more than 3500 MW of new capacity in 2012.

The report linked below has nice graphs and charts showing breakouts by region, country, and offshore vs. onshore capacity.

---Adam

Photo: Norwegian University of Science and Technology

References:

http://www.gwec.net/wp-content/uploads/2013/02/GWEC-PRstats-2012_english.pdf

http://www.winddaily.com/reports/Global_wind_energy_capacity_grows_19_percent_in_2012_999.html

The hand of man

This wonderful satellite photo highlights some of the ways in which we are modifying the surface and depths of the globe in order to keep our civilisation alive. The image was taken over a railyard in the Great Plains of Nebraska, and shows a bunch of trains laden with gleaming black coal to burn in power stations to produce electricity, emitting climate altering CO2 in the process and a semi circular irrigation pattern of a monoculture grain crop, sucking on some fast depleting aquifer (probably the Oglala) in order to keep us fed.

Power and food... satisfying these two needs for the 7 billion humans currently walking the Earth and desiring a comfortable lifestyle is putting the planet's systems under a strain that only major geological events such as asteroid strikes or the eruption of continent sized volcanic provinces ever managed to do before. We certainly live in unprecedented and interesting times.

Loz

Image credit: Digital Globe

New alternative energy being investigated- Osmotic power!

The basics:

Osmotic power relies on a fairly basic physical process known as diffusion. For example, if you have a volume of fresh water in proximity to a volume of salt water, the salt water will move into the freshwater until equilibrium between the two is achieved. This happens regularly in nature, where rivers meet the sea and in the process, energy is created in the form of heat. If this equilibrium is achieved by the introduction of a semipermeable membrane; we call it osmosis. Reverse osmosis, where pressure is applied to the solution at a particular side of the membrane is often used for desalination of sea water for the purpose of creating potable water. Pressure retarded osmosis (PRO), which is used in this application, refers to the energy retrieved from the salinity gradient energy from the differentials in conductivity. In PRO, the optimal output is high pressure, as this would be the equivalent to the energy created by a hydraulic head; like a waterfall.

The idea:

A Norwegian company, known as Statkraft, have been rather quietly working on the world’s first osmotic power plant. With a tiny four kilowatt capacity (barely enough to produce your morning cappuccino), the plant is really quite small; in this case however, size does not matter, what matters is that it works!! The Norwegian Centre for Renewable Energy estimates that the global potential osmotic power is around 1,370 terawatt hours per year- or roughly the current energy consumption of Eastern Europe and Russia.

Statkraft have put in over $12 million USD to develop PRO. Even though it is at its early stages, the force currently generated by the experimental process is quite promising. With pressures at the Norwegian test site reaching 12 bar on the seawater side, "it's like creating an artificial waterfall of 120 meters" (394 feet), according to Statkraft's head of osmotic power, Stein Erik Skilhagen.

Statkraft is now seeking to ramp up its work and researchers around the world are joining in the effort to harness a new form of renewable energy from the saltwater that covers more than 70 percent of the Earth's surface. Global interest in the project is growing. NASA researchers have been working on osmotic systems to treat wastewater on-board spacecraft’s and are now looking into the possibility of utilising PRO to purify water and create energy at the same time. As well as NASA, Hydro-Québec, Canada’s largest hydroelectric facility are partnering with Starkraft for its next stage of development.

The Environmental Pros and Cons:

Osmotic power generation is a very clean energy solution and it is carbon free. The main by-product of the plant is brackish water which can be dealt with cheaply and efficiently.

On the other hand, the impact of large scale facilities on salinity levels or how pre-treatment processes might impact local marine life is unknown and an Environmental Impact Assessment (EIA) must be completed.

The Future:

As with all new technologies, PRO is currently very expensive, but the technology will mature and become more attractive in the coming years. Osmotic energy’s environmental benefits will make it a useful part of the future low-carbon energy mix if costs can be brought in line with other renewables like wind and solar energy.

Whatever the outcome, it is refreshing to see further innovation with regard renewable energy. Although no single renewable energy source will be the overall answer to phasing out fossil fuels, a combination of them can certainly create a more hopeful and sustainable future for our planet.

-Jean

For more information see here:

Starkraft company: http://www.statkraft.com/energy-sources/osmotic-power/technology/

Osmosis: http://bit.ly/RDundy

Reverse Osmosis: http://science.howstuffworks.com/reverse-osmosis.htm

PRO: http://sffe.no/colloquia/arkiv/120927_AlsvikOsmoticPower.pdf

Photograph courtesy of Damian Heinisch, Statkraft