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The Desert Rose Project aims to bring about
reafforestation of desert areas commencing at the coast and using
solar desalination to nurse the forest into existence.
Index
Problems to be addressed
Overview
Technology
Community
Ethical standards for the strategy
Partnerships
Finance
Arboricultural Rationale
Self Sustaining Forest
Solar Stills
Threats
Problems Addressed by Project Desert Rose
1. Global warming, caused by an accumulation of heat retaining
gases in the atmosphere, is the major threat of our time, and
indeed, of all human history.
A global disaster can only be stopped and reversed by a multiplicity
of actions, of which the strategy set out in this paper, creating
a carbon sink by means of reafforestation, is one.
2. Freshwater Scarcity is a major problem in many parts of the
world, and is set to become worse with global warming.
3. Biofuels are required since the supply of fossil fuels is about
to become more scarce in the presence of rising demand, and therefore
fossil fuel price is due to rise markedly. Biofuels have the added
advantage of being far closer to carbon neutrality than the fossil
fuels that they aim to replace. However, they have a major problem
in that they compete with food crops for land, and in some places
valuable rainforest is being destroyed to make land for them.
The strategy in this paper avoids these problems by growing biofuels
on land that is currently desert.
4. Poverty in Less Developed Countries (LDCs) is a great problem
in terms of our common humanity, and also causes knock-on problems
by driving people to burn existing forest in search of land for
subsistence farming, and by driving people to emigrate, which
sometimes results in community tensions in host countries. The
Desert Roses strategy will be to address this by creating good
work, and valuable export commodities, primarily fuel oil, in
LDCs.
5. Desertification is a major problem in many parts of the world,
is set to increase with global warming, and compounds the poverty
problem. Desertification will stimulate wars as people fight over
diminishing fertile land. It is believed that this is one component
of the tragedy in Darfur. Desert Rose, by introducing water into
arid tropical areas, will reverse desertification through reafforestation.
This is an immense task, but the longest journey starts with a
single step.
Overview
The aim is to bring about the afforestation of a desert area
by means of irrigation produced sustainably, primarily from an
array of improved solar desalination units. The strategy is first
to re-create the vital coastal strip of vegetation, and to work
from that strip inwards. Once a certain area of forest has been
created - the precise area will vary with local conditions - the
forest will become self sustaining, producing its own microclimate
and its own cloud cover. With ongoing human care and encouragement,
and by extending the area of irrigation, reafforestation can extend
ever further into the interior year on year.
The new forest can be expected to provide some or all of the
following services:
1. Positive change in the local microclimate
2. Positive changes in the water cycle in the area
3. Positive change in the global climate, by acting as a carbon
sink
4. Biomass fuel
5. Food for humans
6. Forage for animals
7. Building materials
8. Medicines
9. Biodiversity
10. A sense of well being for those who experience the new forest,
those who contribute to it or are conscious of it.
In the process of creating this forest, valuable experience will
be gained in renewable energy, water management and co-operative
action in tropical countries.
Technology
The key to afforestation in this project is the production of
water in tropical coastal regions from sea water by desalination
of sea water. Solar desalination, reverse osmosis and even ground
water (if sustainable) could be used as the supply.
The stimulus to this project was the Cascade Solar Still, an
improvement in the tried and tested single-basin solar desalination
still. It is a low-technology still, capable of being assembled
by personnel with a short period of training. It is expected that
this will produce a quantum leap in the productivity of the solar
still, so that a growing series of stills built along the coast
of any tropical (or indeed, warm temperate) country will produce
significant amounts of water, sufficient to nurse a new forest
into existence. The water will be fed to the new forest through
drip irrigation.
Integral to the performance of the Cascade Solar Still is a pump
designed to pour cool sea water over the still. A newly patented
Flexible Wave Pump will compete with other designs of wave driven
pumps for this role. (See Appendices 1 and 2 for patent specifications
of the Cascade Still and the Flexible Wave Pump). Other types
of pumps, wave powered or otherwise, may be tested.
Wave pumps may also act during the night (when the still is inactive)
to drive reverse osmosis plants, which can supplement the freshwater
product of the stills.
Some stills will be designed to allow brash and spare wood to
be burned beneath them, which will boost their productivity. Charcoal
could be produced in this way.
Other designs of solar distillation may be introduced and tested,
and other forms of renewable technology will be used, for instance,
wind turbines and solar concentrators to provide energy for the
reverse osmosis and reafforestation operation (for instance, for
pumping water further inland as the forest grows) and its service
community. The centre of the operation will evolve into a renewable
energy station, with excess electricity being converted into hydrogen
and oxygen. Other saleable by-products of the process are salt,
chlorine (for sterilisation of town water supplies) and sodium
hydroxide, which can be used to convert oil from the new forest
into biodiesel. Methanol is required for this process, and that
is a by product of the charcoal making process, which can be carried
out in the forest. Heat from the charcoal process can be used
to boost production of specially modified solar stills. If a harbour
is required for transport of goods and people related to the project,
the harbour walls themselves may be designed to generate energy
from the waves.
In this way, the Desert Rose Project will evolve into a model
of a green production centre.
There is a case for allowing fossil fuel use in the beginning
in order to facilitate the difficult start-up period, but fossil
fuel use throughout the project should be accounted for, in order
to be able to know when it has been offset, and should be kept
to an absolute minimum.
The afforestation is not to be carried out as a monoculture,
but as a reconstruction of an ecosystem, albeit an ecosystem designed
to provide certain useful products. The principles of permaculture,
which uses local conditions to advantage, and avoidance of artificial
fertilisers and pesticides, will underlie the project.
Community
Since the reafforestation will take place in lands that are currently
desert, new human settlements must be formed to service the project.
These settlements must be built to very high standards of physical
and social design in the best neo-Owenite traditions to avoid
the social problems associated with new industrial settlements.
The entire community will be designed on ecological principles,
with particular emphasis on water management.
People can use the distilled water before applying it to forest
as grey water. There will be some losses to atmosphere from respiration
and evaporation from cooking, but if all urine, faeces and waste
water are carefully treated and returned to the land, the losses
are insignificant - and the processed water adds a valuable fertiliser
to the soil. Experience gained in careful water management can
be passed on to other communities with water scarcity problems.
One person needs 20 litres per day to cover drinking cooking
and washing, so a 100 sq. metre still could sustain a community
of 25 people.
Ethical standards
The Desert Rose project must have the highest possible ethical
and green standards throughout, not just for their own sake, but
because it will be subject to intense scrutiny from the green
movement. The movement generally is deeply suspicious of large
projects, not without reason, and this will generate high levels
of criticism. There is also a presumption in the mainstream of
the movement that climate change should be tackled primarily by
radically cutting back on CO2 emissions, and that other measures
such as offset and mitigation serve to divert attention from this
effort. The Desert Rose project is based on the premise that it
is possible and desirable to do both at the same time.
There must be a zero tolerance of corruption throughout the project,
from the outset, since corruption is a cancer that undermines
the efficiency of every project it touches. To prevent corruption,
all workers must be paid slightly above the usual rate for the
job they are doing, on the understanding that if they offer or
take bribes, they face instant dismissal.
Partnerships
This huge project will only succeed as a result of successful
partnerships which may include some or all of the following agencies:
1. Central government of the host country
2. Local Government of chosen area
3. Department for International Development (DfID), UK
4. Communities local to the area
5. Glass manufacturers
6. Specialist inflatable dinghy material manufacturers (for the
wave pump)
7. Irrigation system manufacturers
8. NGOs working in the host countries
9. NGOs working with arboriculture
10. Local business leaders and organisers in the host country
11. UNEP
Finance
Financial backing will be sought from charitable foundations,
UN and government agencies. In-kind gifts will be sought from
glass manufacturers, drip feed manufacturers, and other manufacturers
of materials that will be used.
Universities and producers of solar stills and related technologies
will be invited to provide a model of their preferred design for
evaluation in the project.
When the project is established, and an audit of carbon fixation
has been carried out, we can offer a carbon offset service, which
could provide a secure long term flow of income.
Arboricultural Rationale
Transpiration cycle
Trees continually pass water vapour out of the stomata in their
leaves into the atmosphere. This water will condense into clouds
as it rises into cooler air, and fall as rain, to pass into the
soil, there to be taken up again by trees, completing the transpiration
cycle.
A molecule of water will go through this cycle six or seven times
as it passes from the Atlantic to the Pacific over the Amazon
rainforest (Fig 1).
Forests can function as aerial aquifers, conducting moisture
from coastal areas to the continental interior.
Figure 1
[section through South America]
Importance of the Coastal Strip
Most coastal areas have a strip of vegetation, usually palm trees
in tropical areas, where moist winds blowing off the sea stimulate
growth. This strip is vital to the commencement of the transpiration
cycle.
Figure 2 Coastal Strip
[Courtesy Google Earth]
In many places, this strip is disrupted. Figure 3 shows the point
on the West African Coast where the strip of vegetation breaks
down at 17°N 16°W.
It is the aim of this project to restore this coastal strip as
a prelude to reafforestation inland.
Figure 3
[Courtesy Google Earth]
A map of the world in fig 4 shows how deserts seem to spread
west to east, consistent with the westerly flow of jet stream
air currents. At sea level in tropical regions, winds tend to
flow in a north easterly direction, although there is a tendency
for winds at the coast to flow inland due to the land breeze effect,
as continental areas heat up more quickly than the sea, rising
and drawing in cooler air from the sea.
Figure 4
[deserts of the world, courtesy UNEP]
Note that if all the deserts of the earth were reafforested,
they would fix the carbon equivalent to 50 years of American CO2
output, and so would significantly reduce the global warming process.
Figure 5 shows schematically how re-establishing the coastal
forest strip could allow the vegetation to act as a water retaining
system, eventually reforming its own rain cloud. The Green
Belt Movement estimate that dense patches of over 1000 trees
will produce their own cloud. This cloud will increase the albedo
(reflectivity) of the region, resulting in more of the sun's infra
red energy being reflected back into space, helping to reduce
global warming.
Figure 5
Figure 6 shows how the forest could be built up again, working
at the intersection between the coastal strip and an established
area of rainforest that extends inland.
The area of West Africa between Northern Senegal and Southern
Mauretania meets this criterion.
Planting strategy
Planting will be carried out on ecological principles, preferably
under the guidance of a permaculture expert.
All tree planting will be accompanied with appropriate fungal
mycelia in order to boost tree health.
Experiments will be made to measure the potential of other natural
methods of boosting growth, such as bio-char.
The solar stills will be placed to allow a strip of undisturbed
land between them to permit the natural movement of flora and
fauna from to and from the water's edge.
The reafforestation will be a diverse culture, not a monoculture,
which means that collection of the forest products will be manual
rather than by machine. This will provide seasonal employment
for nearby towns. As well as the oil palm, other more drought
resistant species can be introduced.
Careful consideration of the invasive potential will be given
to any non-native species introduced, and at the first sign of
invasiveness, that species will be eradicated.
The water table will be carefully monitored, since some deep
rooted species can cause lowering of the table, to the detriment
of local wells.
Jatropha
Jatropha is an oil bearing bush that can grow in arid conditions.
It is therefore less dependent on the product of the solar still,
and can act as the pioneer species of the advancing forest, together
with companion plants which may provide support.
Argan Trees
Argania Spinosa is a native of the semi-desert of South west Marocco.
It has deep roots and produces valuable cooking oil, and may be
another candidate as a pioneer species in the project.
The Self Sustaining Forest
Mature trees access deeper groundwater, so distilled water irrigation
will only be needed for nursery stage of the reafforestation,
and afforestation can extend year by year from the same still.
Extended irrigation pipes will require pumps to take the water
further on.
Forest cover will aid retention of water, and create rain cloud,
increasing albedo and reducing transpiration losses.
Mulching with ground cover by natural and/or plastic materials
will reduce evaporation.
The trees will create a cooler land surface , and will encourage
rainfall to reach the ground, as in some conditions rain can evaporate
before reaching the ground.
The new forest can become self sustaining and self propagating,
given human help
Solar Stills
See appendix 1 for the design of Cascade solar still. Other sources
of water will be from reverse osmosis and rainwater collection.
Solar desalination stills are an established and successful technology.
Their deployment and development has been inhibited up to now
by their relatively slow production rate, and the perception that
oil for distillation was cheap, benign and plentiful. The single-basin
still is the standard, although many more complex arrangements
have been put forward. As Project Desert Rose grows, it will be
possible to put a variety of these alternatives to the test.
There are some hybrid designs of still where the sun is used
to pre-heat water, and the process is completed by electricity.
A plentiful supply of wind turbines will enable this technology
to be assessed. One still may be set aside for heating by biomass,
with a fire set beneath a metal plate to speed evaporation.
Tiwari , Singh and Tripathi have an on line review here: http://eprint.iitd.ac.in/dspace/bitstream/2074/1230/1/tiwaripre2003.pdf
Water Productivity
The productivity of the basic single basin solar still is quoted
as 1 cu metre (1,000 litres) of water per sq metre of still per
year, though Solaqua claim 2,000 litres per sq metre per year
for their system.
The productivity of the still can be improved by using it as a
rainwater harvesting surface during the rainy season. In West
Africa, provision of a cistern could add another 50 cubic metres
of water to the productivity of a 100 sq metre installation..
Rainwater Harvesting
Dakar rainfall = 1.38 mm/day
Most falls in July - Sept
100 sq metres of glass needs 50 cu metre cistern
= 50% increase in productivity of still
Therefore the productivity of a basic 100 square metre still,
including rainwater harvesting, falls between 150 and 250 cubic
metres of water per year.
Energy productivity
We will now find how this amount of water translates into oil
palm, not because a monoculture of oil palm is envisaged, but
in order to find if there is a potential energy payback.
Given that the oil palm requires 2-5 mm of rainfall a day, the
lowest estimate is
Distillate 2.5 litres/day/sq metre
= 250 litres/day/100 sq metre still
The rainwater collection (50 cu metres a year) equates to 137
litres a day, so the total water production amounts to 387 litres/day.
= 387,000 ccs
= 774,000 sq cm of land coverage at 5 mm/day
= 77.4 sq metres
=0.0077 hectare of oil palm supported by a 100 sq metre still.
Given that one hectare of oil palm can yield up to 6000 litres
of oil a year,
the 100 sq meter still can support 46.4 litres of oil a year,
using the least favourable assumptions.
Using the most favourable assumptions of 6 litres/water/day/sq
metre of still,
100 sq metre still produces 600,000 cc's per day,
equivalent to 3,000,000 sq cm of rain cover at 2 mm/day
= 300 sq metres
= 0.03 hectare
which would give 180 litres of oil a year.
Rainwater harvesting would boost this by 25% (200 cu/metres of
water/y > 250)
giving 225 litres of oil/year for a 100 sq metre still.
Note that these calculations are for present technology, and
do not take account of the improvements from the Cascade still.
Energy Payback calculations
If the still is made of sun-baked mud bricks, the major part of
the embodied energy in the still will be in the glass. There will
also be embodied energy in the plastic tubing for conducting water,
and other fittings, and concrete construction would entail significant
energy costs.
The embodied energy (ee) of 100 sq metres of glass = 4,800 MJ
(Glass ee = 16 MJ/Kg
100 sq m. at 3 mm thick = 0.3 cu. metre
= 300 Kg = 4,800 MJ)
Specific Gravity of palm oil = 0.924
Calorific value of Palm Oil = 30 MJ/Kg
Taking the pessimistic assumption
46.4 litres of oil = 42.9 Kg
=1287.3 MJ
= 3.7 year energy payback for the glass.
Taking the optimistic assumption,
225 litres of palm oil gives 6237 MJ per year
= 0.77 year energy payback (9 months)
A 30 year life is quoted for a solar still.
If the other peripherals of the still (hose, pump fittings) double
the embodied energy, the paybacks increase from 18 months to 7.4
years.
For simplicity, the calculation has focussed solely on the notional
crop from an oil palm plantation. The plantation will also produce
biomass, and since it is part of a mixed culture, other products
will accrue.
These calculations are based on present technology. The exact
improvement from the Cascade Still is to be determined.
Threats
1. Failure of nerve
This is an immense project, which will require a long period of
investment before strong results are apparent. On the other hand,
improvements in terms of green cover will be visible even in the
first few years, but by the same token, browning of these green
shoots is quite possible, and this could easily be seized on by
red top journalists as "Ground Nut Scheme II", so press
launches will have to balance caution with enthusiasm.
Spreading the risk between many partners means that they may
lose interest. A strong liaison officer is the antidote to this.
2. Corruption
The zero tolerance policy toward corruption is the only way to
eradicate this cancer which undermines projects by whittling away
at project monies as they pass down the chain so that the sharp
end action cannot be completed. The United Nations Convention
against Corruption is an excellent standard to set within the
organisation,
The problem can be summed up in two quotes. Marx said: "The
key to success in business lies in honesty: if you manage to get
rid of it, you've done it." Bertold Brecht: "Honesty
begins with a full stomach." The first is from Marx G, not
Marx K, and should therefore not be taken as gospel. The Brecht
quote gives the key to the anti-corruption drive: we must pay
all our members well, but let them know that they will be dismissed
mercilessly if they engage in corrupt practices.
3. Failure of plant growth
We must accept that failure will be a necessary part of this experiment.
Not all species of plant will grow in all soils. Some plantings
are bound to fail, and this chould be seen as a learning opportunity
rather than as a setback. This is the advantage of permaculture,
where growth is mixed, so that rather than viewing vast swathes
of failed planting, we will see small patches of failure, which
can be recycled by being burned under desalination stills designed
for that purpose.
4. Human problems
As well as corruption, dissention and disagreements are likely
from time to time in what is essentially a colony situation. This
can only be offset by careful social design, and facilitating
of best group processes, without falling into the trap of social
navel gazing.
5. Sea level rise
The project has to be set at the edge of the sea, and the sea
may be set to move inland. The project hardware is capable of
being dismantled and reassembled. If the planted forest is killed
by frequent flooding, at least the energy value of the biomass
can be recovered in the new location. Although the prime candidate
site is West Africa, the downside of this location is that it
is low lying for many miles inland. Depending on predictions and
observations of sea level rise, and on the size ands commitment
of the global economic response to the threat of global warming,
the project may make a commitment to West Africa as a statement
of faith in our ability to succeed, or may choose another location
where it is possible to retreat to higher ground.
Appendices 1 & 2
Patent specifications (currently unavailable)
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