Archive for the ‘– distributed energy’ Category

Solar energy powers South Australia’s desert Sundrop Farms

November 21, 2016

Desert farm grows 180,000 tomato plants using only sun and seawater http://www.mnn.com/your-home/organic-farming-gardening/stories/desert-farm-grows-180000-tomato-plants-using-only-sun-and-seawater

Farms that grow food in arid deserts, without groundwater or fossil fuels, could be the future of agriculture. BRYAN NELSON October 10, 2016, No soil, no pesticides, no fossil fuels, and no groundwater. And yet, a thriving farm in the heart of the arid Australian desert. How is this possible?

An international team of scientists has spent the last six years fine-tuning a system that pipes seawater in from the ocean and desalinates it using a state-of-the-art concentrated solar energy plant. The water is then used to irrigate 180,000 tomato plants grown in coconut husks instead of soil, kept in a network of greenhouses.

The result is Sundrop Farms, a commercial-scale facility located just off the Spencer Gulf in South Australia that began construction in 2014. Today it’s producing an estimated 17,000 tons of tomatoes per year to be sold in Australian supermarkets.

Given the increasing demand for fresh water around the world — a problem that’s particularly apparent in the sunburned landscape of South Australia — this might just represent future of large-scale farming, especially in coastal desert regions that have previously been non-arable.

The heart of the farm is the 23,000 mirrors that reflect sunlight towards a 115-meter high receiver tower. All of that concentrated sunlight produces an immense amount of power, up to 39 megawatts. That’s more than enough to cover the desalination needs of the farm and supply all the electricity needs of the greenhouses.

The seawater, too, has other purposes besides just irrigation. During scorching hot summers, seawater-soaked cardboard lines the greenhouses to help keep the plants at optimal temperature. Seawater also has the remarkable effect of sterilizing the air, meaning that chemical pesticides are unnecessary.

All in all, the facility cost around 200 million dollars to get up and running. That might sound excessive, but in the long run the facility should save money compared to the costs of conventional greenhouses that require fossil fuels for power. It’s a self-sustaining, cost-efficient design so long as the initial investment can be provided. Facilities similar to the Australian one are already being planned for Portugal and the U.S., as well as another in Australia. Desert areas like those seen in Oman, Qatar and the United Arab Emirates could be next in line.

“These closed production systems are very clever,” said Robert Park of the University of Sydney, Australia, to New Scientist. “I believe that systems using renewable energy sources will become better and better and increase in the future, contributing even more of some of our foods.”

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The future of energy – decentralised renewables

November 21, 2016
Why the Future Belongs to Decentralized Renewables, Not Centralized Hydrogen and Giga-Scale Nuclear November 18, 2016 by Energy Post

“……….Let me develop the real reasons why conventional renewables are likely to emerge as the dominant primary energy sources in the first half of the
21st century. The fundamental advantages of renewables, as revealed by practical experience in China as well as in industrialised countries like Germany where an energy transformation is well under way, are these.As they scale renewable energies do not present greater and greater hazards. Instead they are relatively benign technologies, without serious riskThey are clean (low to zero-carbon); they are non-polluting (important in China and India with their high levels of particulate pollution derived from coal); they tap into inexhaustibleenergy sources; and they have close-to-zero running costs since they do not need fuel. They are also diffuse, which should be viewed as an advantage, since this means that renewable sources are decentralised, and can be harvested by both large and by small operations. So they are eminently practicable.Some advantages of renewables are not at all obvious and need to be made explicit. Fundamentally, they are scalable. They can be built in modular fashion – one solar panel, 100 solar panels, 1000 solar panels. As they are replicated in this fashion so their power ratings continue to rise, without complexity cutting back on efficiency. This cannot be said of nuclear reactors, which have an optimal operational size – below which or above which the plant under-performs.

Moreover as they scale they do not present greater and greater hazards. Instead they are relatively benign technologies, without serious risks.

 

When they use hazardous materials, such as the cadmium in Cd-Te solar, the solution would be to recycle materials in order to minimise the use and waste of virgin materials.

Most importantly, the superiority of conventional renewables lies in their cost reduction trends which are linked to the fact that they are always the products of manufacturing – and mass production manufacturing, where economies of scale really play a role. This means that they offer genuine energy security in so far as manufacturing can in principle be conducted anywhere. There are no geopolitical pressures stemming from accidents of chance where one country has deposits of a fossil fuel but another does not. Manufactured devices promise an end to the era in which energy security remains closely tied to geopolitics and the projection of armed force. As Hao Tan and I put it in our article published in Nature, manufacturing renewables provides the key to energy security.

Manufacturing is characterised by improving efficiencies as experience is accumulated – with consequent cost reductions captured in the learning or experience curve. Manufacturing generates increasing returns; it can be a source of rising incomes and wealth without imposing further stresses on the earth. Add to these advantages that renewables promise economic advantages of the first importance: they offer rural employment as well as urban employment in manufacturing industry; they offer an innovative and competitive energy sector; and they offer export platforms for the future.

The real driver of the renewable energy revolution is not government policy, or business risk-taking, or consumer demand. It is, quite simply, the reduction of costs

This is to list the advantages of renewables without even mentioning their low and diminishing carbon emissions. Indeed they offer the only real long-term solution to the problem of cleaning up energy systems.

With all these advantages, it is little wonder that China and now India are throwing so much effort into building renewable energy systems at scale. These are not exercises undertaken for ethical or aesthetic purposes, but as national development strategies of the highest priority.

So the real driver of the renewable energy revolution is not government policy, or business risk-taking, or consumer demand. It is, quite simply, the reduction of costs – to the point where renewables are bringing down costs of generating power to be comparable with the use of traditional fossil fuels, and with the promise of reducing these costs further still. Supergrids are also being promoted for renewables, but these are very different conceptions, based on integrating numerous fluctuating sources in IT-empowered grids, offering the same practicable, scalable and replicable energy future.

Against these advantages, the obstacles regularly cited are small indeed. There is the fluctuating nature of renewables, which can be addressed by various forms of systems integration (smart grids, demand response) and of course through energy storage, which is moving into the same kind of cost reduction learning curve that has characterised solar and wind power, promising rapid diffusion of both commercial and domestic energy storage units. With rapidly falling costs of storage providing the buffer that can even out fluctuating levels of generation, there is no further serious argument against renewables……..

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This article is based on a scientific paper by John A. Mathews, Competing principles driving energy futures: Fossil fuel decarbonization vs. manufacturing learning curves, which was published in Futures in November 2016 (.http://www.sciencedirect.com/science/article/pii/S0016328715300227)

John Mathews is author of the Greening of Capitalism: How Asia is Driving the Next Great Transformation”, published by Stanford University Press: http://www.sup.org/books/title/?id=24288. His latest book, “China’s Renewable Energy Revolution” (co-authored with Hao Tan) was published by Palgrave Pivot in September 2015: http://www.palgrave.com/page/detail/chinas-energy-revolution-john-a-mathews/?isb=9781137546241.

See his author’s archive on Energy Post.

Affordable distributed solar energy for the world’s poor

June 4, 2012

Barefoot Power’s products are brightening up the lives of those with limited or no access to grid power.  Products range from single desk lamps to complete kits for use by homes, clinics and schools. With good links to microfinance organisations and exceptional customer care, Barefoot has sold more than 400,000 lanterns and lighting kits to two million rural poor in Africa,Asia Pacific, India and the Americas. 

Solar power pioneer wins global green energy award, PR Wire 1 June 12,  A company specialising in providing affordable solar power products to remote rural communities has won a coveted Ashden Award for its work in Africa.

Barefoot Power was awarded some £20,000 in prize money at a prestigious ceremony in London this evening after joining other Award winners at a meeting with His Royal Highness the Prince of Wales at Clarence House in the morning.

The Ashden judges said: “With its astonishing sales figures, Barefoot is a fantastic example of a market-led solution to bringing renewable electricity to Africa’s rural poor. Through its network of micro-entrepreneurs it is overcoming the barriers of how to access remote communities and how to make solar power affordable.” (more…)

Renewable energy storage

June 4, 2012

In-Depth: Germany’s 22 GW Solar Energy Record Clean Technica, MAY 31, 2012 BY THOMAS“…….Millions of Batteries in Buildings — Utopian? …… it is very easy to show that it’s just a matter of time until the combination of energy storage for homes with rooftop solar energy and/or small-wind becomes viable and even profitable.

Today, there are still about 6.4 million oil tanks in homes and buildings all over Germany storing energy in the form heating oil. Installing such a tank costs several thousand Euros today. So, why shouldn’t independent power producers start putting up new forms of energy storage in the same numbers as soon as it makes economic sense?

How would 6 million home storage systems change the energy system? Well, 6 million 10 kW / 25 kWh would mean a distributed storage system with 60 GW maximum output/input and 150 GWh of capacity. That’s already enough storage for 10% of the current daily consumption, more than enough to power all German households through the night. It’s also coming a long way to fill the gap between renewable baseload power (hydro and biomass) and variable sources like wind and solar.

That 10-kW/25-kWh battery is not fiction by the way. It’s quite similar to the battery pack that powers the Nissan Leaf right now, Just one battery that will soon reach production volumes in the hundreds of thousands as factories in Japan, Europe, and the US crank up production by 2013.

It’s true that the $15,000 price tag for the battery is too high right now. But, since all kinds of competitors are investing in this market, economics of scale, innovation and optimization will certainly reduce the cost of such batteries in the coming years. In the case of multi-kWh batteries, this development is a lot more obvious than what happened with the price for solar cells just 7 years ago. The fall of prices surprised many analysts back then. Today, prices for solar cells are 70%-80% cheaper than what they were in 2007, putting the cost of solar systems well below $2 per Watt in Germany…. .. https://mail.google.com/mail/u/0/?shva=1#inbox/137a6ed1432cd545