Green Frontier Mission
To transform degraded environments into biodiverse ecosystems with thriving human settlements, while reducing atmospheric CO2 to pre-industrial levels.
A green and pleasant world where all life thrives.
The Green Frontier is a collaborative effort to freely disseminate findings of best practice about creating thriving green productive land without chemical use or the reliance on fossil fuels. Please distribute the content of this site widely, the only thing we ask is that you acknowledge the Green Frontier when doing so.
If you share our vision and would like to contribute to the Green Frontier toolkit, please contact admin [at] greenfrontier [dot] com.
Craig Embleton is an ecologist and food forest activist. He studied biology, specialising in agriculture and ecology at the University of Hertfordshire in the UK during the 80’s. During the 90’s, as a deeply indebted post-student employee, he sold his soul and worked as a field trials specialist for a number of multinational agro-chemical companies. During the 00’s he deeply regretted being involved in that industry and resolved to undo their damage through agro-ecological approaches to food production.
For over 10 years Craig has researched alternative approaches to productive agriculture, investigating the idea of true green revolution – one that doesn’t rely on chemicals, fossil fuels and depleting natural resources.
Craig has recently completed an MSc in Environmental Architecture with CAT and the University of East London. In 2009 he completed a Permaculture Design Course in Jordan and now is looking to secure funding to progress the desert restoration work researched in his thesis.
The following works by Craig Embleton are licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
What is the potential for reducing atmospheric CO2 levels through solar-desalinated irrigated vegetation of the Sahara and Arabian deserts?
Abstract: 9.8 gigatonnes of oil-equivalent fossil fuel were consumed in 2009 (BP, 2010). The negative aspects of anthropogenic climate change due to CO2 emissions have been documented by Stern (2007). This thesis will consider a proposal to enhance the terrestrial carbon sinks, rather than focusing on reducing carbon emissions.
This thesis used existing data to investigate the potential of solar-desalinated water to irrigate the MENA region with a view to growing vegetation in the Sahara and Arabian deserts. The proposal being that this vegetation would lower atmospheric CO2 by creating a net carbon sink. Eucalyptus grandis x urophylla was chosen as the species to model this proposal, due to its relatively well-researched growth rate and water requirement. It is acknowledged, however, that this species is non-indigenous to the MENA region and a monoculture of this fast-growing species, or any would not be recommended in reality.
The thesis calculated how much carbon could potentially be sequestered both in the vegetation and the soil of a Eucalyptus grandis x urophylla forest, on an estimated area of 8.4 million km2 across the MENA deserts. Water required to irrigate this forest was calculated from existing research. The electricity demand to provide that water through desalination of seawater, mostly through reverse osmosis, and to supply the water to the trees by pumping it across the desert in pipes was then calculated. The thesis reviewed how much electricity could be generated using concentrating solar power in the MENA region and found there would be surplus energy generated, beyond that required for the desalination and irrigation processes. The area of land required for the parallel troughs or linear Fresnels used to provide the electricity was also calculated from the land use efficiency of the CSP units and the direct normal irradiation falling on an area of land. The costs, benefits and possible sources of income from this project were discussed.
Results from this thesis suggest that a forest of Eucalyptus grandis x urophylla occupying 8.4million km2 of MENA deserts could be capable of sequestering 8 – 14.3GtCyr-1 in the vegetation and upper-soil profile. Non-land-use-change anthropogenic carbon emissions are currently 8.7Gtyr-1. The forest would require 7,560 – 8,400km3 water yr-1 for irrigation, which would require 56,144 – 62,553TWh electricity yr-1 to desalinate. Electricity could be supplied by CSP units covering 324,532 – 579,194km2. Major project costs included CSP units, RO plants and pipework. Benefits included ecosystem services, timber and carbon credits.
Download thesis as Adobe PDF.
Can the DESERTEC concept and the proposed EU-MENA supergrid facilitate contraction and convergence of carbon emissions between the nations involved?
Abstract: The DESERTEC concept and the proposed EU-MENA supergrid will enable great cuts to be made in carbon emissions from developed nations,
and reduce projected carbon emissions from developing nations. But the current DLR studies rely too much on fossil fuel for back up. The reductions in carbon
emissions for electricity production will not allow the EU-MENA nations examined to contract and converge to safe levels of total carbon emissions. The poorer
developing nations in the study such as Yemen must develop along a different path to that of wealthier nations. They must adopt the process of ‘leapfrogging’
whereby they adopt new technologies and skip the outdated fossil-fuel-based development model. Concurrently the wealthy nations must pursue a paradigm shift in their current non-electrical energy use – such as transport.
Can human sewage provide the feedstock for biodiesel production by photoautotrophic microalgae?
Abstract: The idea of transforming sewage from a problem is a solution is enticing. However, there have been few studies conducted on the
specific use of sewage to provide the feedstock for biodiesel production. Even the aquatic species programme changed focus from sewage to agricultural fertilizers early in the programme. Since then most commercial and academic research into algal-biodiesel production has concentrated on the growth of the algae in specifically created growing media. However, there is a long history of exploiting algae in waste stabilisation ponds and there has been some promising research on using urine for algae production. Perhaps specifically created media should continue to be used while the photobioreactor algal-biodiesel industry reaches maturity, and wastewater harvesting should concentrate on developing biodiesel from wild species from waste stabilisation ponds and raceway ponds. Meanwhile the problem of sewage pollution, particularly in the developing world must be tackled. When town planners are considering new infrastructure perhaps this is an opportunity to build high-rate sewage ponds or raceway ponds near fossil fuel power stations and incorporate algal carbon capture.
Could domestic photovoltaics provide the electricity needed to meet household demand and power a family car in the UK?
Abstract: A 4 kWp photovoltaic module installation on the south-facing roof of the case study house could generate more than enough electricity
to supply the net annual household electricity and power an electric car. The roof had sufficient space to accommodate a far larger array. The mean UK household consumed more than twice the electricity than the case study house and it would also consume over a quarter more electricity to power an electric car. A 6 kWp installation covering 32 m2 would provide 97% of the total electricity needs – assuming the azimuth and roof inclination were the same as the case study house.
Could new build houses in the UK be carbon negative in terms of embodied energy?
Abstract: If material is selected from renewable sources, and CO2 assumed to be sequestered permanently, it is possible to construct carbon
negative buildings in the UK. If my 1970’s suburban house had been built to Green Guide best practice standards 2009, using some recycled materials, it
would have been carbon negative. Ben Law’s house is carbon negative, but not designed for mass production. The wide scale adoption of straw bales as infill
for timber-frame builds and reducing the use of plastics, concrete and brick greatly reduces the embodied energy. The ModCell™ Balehaus™ showed great potential.
Based on company data, the house is substantially carbon negative.
How much organic food could be produced in UK gardens and what environmental benefits would that bring? (The End of Suburbia or the beginning of the Good Life)
Abstract: Widespread adoption of biointensive kitchen gardening techniques coupled with the extensive planting of food forests in private gardens could substantially improve the UK’s self sufficiency in food production whilst reducing fertilizer, pesticide usage and GHG emissions. All fruit, vegetables and potatoes could be garden produced. Wildlife would benefit through increased habitat availability throughout urban areas and potentially more habitat available in the countryside. To maximise benefits however people would need to change their behaviour and begin enjoying indigenous in-season produce rather than pre-packaged air-freighted produce. They would also need to actively participate in land-share schemes to match gardeners with land.
Could composted organic waste, including human excreta, replace chemical fertilisers on UK farms?
Collecting and composting all organic wastes including human excreta, could supply the same amount of phosphorus and potassium to tillage land that is currently applied by chemical fertilisers. Alternative sources of nutrients need to be applied to grassland.
There would be sufficient compost to match the rates used commercially on Sheepdrove organic farm. Nitrogen would by supplied in lower quantities to chemical fertilisers, however, it would, together with phosphorus and potassium, be in a slow release form. SOM would increase and soil structure improve wherever compost was applied. Phosphate and potassium resources would be conserved and there would be energy savings by not manufacturing nitrogen fertilisers. Thirty-five percent less domestic potable water would be needed and a major stream of pollution would be eliminated. Critically, soil carbon loss would be reversed.
Straw-bale or hemp/lime construction: which is more appropriate for an environmentally responsive low-density housing development in Suffolk?
Abstract: Straw is abundant in Suffolk and the county could grow enough hemp to supply its housing requirements. Facilities exist in Suffolk to process 95% of the hurds required to supply the entire housing need of the county. Suffolk’s climate is suitable for both straw-bale and hemp/lime buildings, externally rendered with lime plaster. Both building methods would bring local economic benefits, are suitable for amateurs and professionals alike and produce structurally sound buildings. Both types of building have similar air quality properties, but straw-bale buildings may have better soundproofing and thermal performance than hemp/lime, and brick-and-block, but results are inconclusive.
Minimising lime use minimises the environmental destruction caused by mining, and the associated CO2 emissions. Straw-bale buildings used less lime than hemp/lime buildings and usually sequester more CO2. Only the best-case scenario for a hemp/lime building with very thick walls could match the net CO2 sequestration of a straw-bale building. Considering all factors, straw-bale building is more appropriate than hemp/lime for the construction of low-density dwellings in Suffolk.