Earthships 6 principles

Earthships
6 Principles
Presentation by InterConnected
Earthships, 6 Principles by Darren Roberts is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Based on work at https://interconnected.me/.
Permissions beyond the scope of this license may be available at https://interconnected.me/terms.

1. Thermal/Solar (a) Heating & (b) Cooling.
2. Solar & Wind Electricity.
3. Contained Sewage Treatment.
4. Building with Natural & Recycled Materials.
5. Water Harvesting.
6. Food Production.
6 Principles
6 Principles, Presentations on Youtube

Natural Air Conditioning
Solar Angle Basics
References
Appendix
6 Principles, Presentations on Youtube

6 Earthship Principles : Presentations on Youtube
Principle #4. Natural &
Recycled Materials
Principle #6, Food
Production
Principle #5, Water
Harvesting
Principle #1, Thermal /
Solar Heating & Cooling
Principle #2, Solar & Wind
Electricity
Principle #3, Contained
Sewage

Example: Earthship-Style Room
1 (a) Solar Heating
aka - Solar Gain / Passive
1 - Solar / Thermal Heating & Cooling

1 - Solar / Thermal Heating & Cooling Video Presentation
Video on Youtube - Presentation available
here:-
Earthship Principle #1, Thermal / Solar
Heating & Cooling
Presentation available at InterConnected

1 (a) - Solar Heating. Aka “Solar Gain”
Sunlight enters the building during the day.

The floor, walls, etc absorb energy,
getting hotter during the day

This ‘stored energy’ is then useful during colder
hours, such as night-time, winters etc.

The Problem, in Taiwan:-
Too much heat. Usually for 8
or 10 months every year.

So We’ll look at ways of
reducing energy from the sun
later such as roof overhangs,
cable awnings, shades, blinds,
curtains etc..

Which Materials, would be better
for absorbing energy?
Air? Stone? Metal? Water?
Why? In what situations?
A QUESTION:-

End of Solar Heating
Any Questions?
Solar Chimneys -
Wikipedia link.
More Info on Solar Gain -
Wikipedia link.

1 (b) - THERMAL COOLING.
Aka “Convection Engine”
1 - Solar / Thermal Heating & Cooling

We can use Heat, to cool
buildings.

Hot air, rises.

Using a Vent, in
the roof, we can
allow Hot Air to
escape

As the Hot Air inside the building escapes
through the vent in the roof -
Fresh air is drawn in through a ventilation pipe.

The fresh air from outside, is cooled as it loses
heat to the earth underground.

This creates a flow of air, driven by Hot Air rising
up through the Roof Vent.
Also search for ‘Solar Chimneys’ & take a look. Old, effective Tech ;-)

ResearchGate Link:
From this data, we can
see that Ground
Temperature at a Depth
of 1 metre can vary
between 10 to 30 C.
At a Depth of 2 metres,
Ground Temperature
varies between
18 to 25 C.
Florides, Georgios & Kalogirou, Soteris. (2019). Annual ground temperature measurements at various depths.

1 THERMAL PERFORMANCE.
The red Area, and Blue
area, show
Temperatures
throughout the year.
‘No fuel’ - the Blue Line -
this is the temperature
with no additional
heating.
‘COMFORT’ - the Red
Line - shows how little
fuel is required to heat
or cool an Earthship.

More Info on Temperatures Underground -
ResearchGate.
More Info on Solar Gain -
Wikipedia link.
End of Thermal Cooling
Any Questions?

2 - Solar & Wind Electricity

here:-
Earthship Principle #2, Solar & Wind
Electricity
2 - SOLAR & WIND ELECTRICITY.

Solar Panels
These come in 2 types:
a. PV (photovoltaic)
b. Thermal
Images:
Solar Panel, Wikipedia, license.
Solar Heater, Wikipedia, license.
Batteries, Wikipedia, license.
Both types of Solar panel are common in Taiwan.
1) Solar Photovoltaic
For Electricity, typically feeding
a battery bank.
2) Solar Thermal
For Hot Water, stored in a hot
water tank.

Solar Photovoltaic
a battery bank.
Works in sunny & cloudy
conditions.
Electricity Storage
Typically in batteries. Some examples:-
● Lead Acid - (car batteries)
● Lithium ion (in your phone / tablet / Tesla Power Wall)
● Nickel iron (possibly one of the best for the environment,
and repeated deep discharge does not reduce life
significantly - wikipedia link
● We can also use Water, as well as Air, to store energy from
Solar Panels. We’ll come to that in a later slide ;-)
Images: Solar Panel, Wikipedia, license.

Solar Thermal
For Hot Water, stored in a hot
water tank.
Solar thermal panels can be
placed
a) On the roof with an
integral tank(s)
b) On the ground outside,
feeding an integral hot
water tank, or a water
tank in the building.
Image: Solar Heater, Wikipedia, license.

Wind Turbines
a battery bank.
1. Each type of wind turbine
has pros & cons with
regard to efficiency at
different wind speeds
2. Reliability
3. repair & maintenance
4. cost of installation
Etc etc….
Image: Wikipedia - Turbine , license.

Types
There are 2 basic
types of wind
turbines
1. Vertical Axis
2. Horizontal
Axis
Wikipedia link
Turbines animation By Ssgxnh - Own work, Public Domain,

Wind Speed
Some types of wind turbine will
spin with slower wind speeds.
*see at 1m 14s.
Safety / Maintenance
They may also not ‘blow up’ or
disintegrate by spinning out of
control in a Typhoon.
Video: Earthship Biotecture Youtube Channel

OTHER OPTIONS TO GENERATE
POWER
Graphic by , https://www.theengineer.co.uk/pumped-hydro-storage/
Pumped Hydro with Micro Turbine.

FIRST - USE LESS.
A more efficient home,
needs less energy.
Earthships use a lot less energy than
conventional housing.
Some figures from the UK in 2014.
So we can use the figures in the blue
sections.
*Comparison is not direct, but we
know in the UK people mostly use
Gas for heating.
Source: graph_source kWh: 9,000 *13,500 19,000

EARTHSHIP ANNUAL
HEATING & COOLING.
Earthship figures are from 600
kWh to 2,600 kWh annually.
600 kWh is for the Global Model
Earthship, which is the most
efficient Earthship design.
Less efficient Earthship designs
consume up to 2,600 kWh.
Data chart : Earthship NZ
kWh: from 600, to 3,000.

Earthship Figures are for
‘heating & cooling’ annually
(Global Earthship Model)
UK figures - we have used the
figure for Gas consumption, to
exclude lighting & other
appliances.
So, we can ‘guesstimate’ that
an Earthship will use between a
Fifth (1/5th) and a Twentieth
(1/20th) of the energy of a
conventional home.
13,500 / 600 = 22.5. 13,500 / 2,600 = 5.2

So, with this said…..
What impact does that have on our
Solar, or Wind Turbine
requirements?
Basically, we need a lot less
infrastructure to provide the energy
required by the home.
E.g. - If a ‘medium sized’ house in
the UK needed 22 solar panels, a
‘Global Model’ Earthship would need
1.
Again, ‘guesstimates’, but illustrates
the point.
Images: Solar Panel, Wikipedia, license.
Regular House - 22 panels Earthship Global Model - 1
Earthship - Uninsulated, no
Berm, no Greenhouse - 5

2 - SOLAR & WIND
End of Solar & Wind
Any Questions?

3 - Contained Sewage Treatment

3 - CONTAINED SEWAGE TREATMENT.
here:-
Earthship Principle 3, Greywater and
Blackwater Treatment

‘Waste’ water in Earthships, is not seen as ‘waste’, but is re-used for watering plants, flushing toilets etc.
We are working with 2 Types here - 1) ‘Greywater’, and 2) ‘Blackwater. First, let’s look at Greywater.
1) What is ‘Greywater’?
Water from :
● Showers
● Hand-basins etc.
Images: wikicommons: shower (license), wash basin (licence) Presentation by InterConnectedImages: wash basin, licence | shower, licence

Instead of throwing this
water away to the drains
outside -
From the showers &
hand-basins, the water
flows to a Filter, at one
end of the Planter.
These filters have been
made from peat, gravel,
sand & other materials.
Greywater
Bathroom
Filter

After filtering, the water
runs through the planter,
feeding the plants.
The roots of the plants
help to clean the water -
one of the ways the roots
help is by oxygenating the
soil and water.
(Oxygen = highly reactive)
Greywater

Greywater
After the roots of the
plants have helped to
clean the water - there is a
well, and a pump at the
other end of the planter.
This water is then clean
enough to filter & fill our
toilet cisterns & use for
flushing our toilets.
Greywater

These planters can
produce plenty of food.
Herbs, tomatoes, and
even banana trees have
been spotted in some
houses;-)
Greywater

Kitchen Sink
Some Earthships have also used the water from
the kitchen sink - extra grease / particle traps are
required for this.
Not everyone likes cleaning the grease traps
though, so I believe it is more common now for
kitchen sink water to go out with Blackwater.
The Septic Tank then deals with it.
Greywater

2) What is ‘Blackwater’
Blackwater comes from our toilets.
We typically need to process blackwater through a
Septic Tank, or Reed Beds etc, before allowing it to
flow back onto our land, and into our Groundwater /
water table.
(Kitchen Sink waste water often goes together to the
Septic Tank)
Images: wikicommons: toilet (license)
2) Blackwater
Presentation by InterConnectedImage: toilet, licence

2) Blackwater
Water from toilets typically
goes to a normal Septic Tank.
Septic Tank

2) Blackwater
The overflow from the Septic
Tank runs into an exterior
rubber-lined Botanical Cell
Septic Tank
Exterior Rubber-lined
Botanical Cell

2) Blackwater
The Botanical Cell can be used
for growing landscaping plants.
I have heard of people using it
for fruit trees - not herbs / salad
vegetables.
Plants with trunks - maybe
guava / papaya / banana /
lemon would be suitable to
test.
Septic Tank
Exterior Rubber-lined
Botanical Cell

2) Blackwater
If intending to use for food, the
plants / soil / food cropped should
be tested.
It is cheap enough in the U.S. to
send soil & fruit samples off to the
laboratory to ensure the food is free
of pathogens & fit for consumption.
I assume similar tests are available
in other countries.

3 - CONTAINED SEWAGE TREATMENT
End of Sewage Treatment
Any Questions?

4 - Building with Natural &
Recycled Materials

4 - NATURAL & RECYCLED MATERIALS
here:-
Building with Natural and Recycled
Materials, Earthship Principle 4

4 - NATURAL & RECYCLED MATERIALS
‘Natural’ and Recycled materials is a pretty broad topic, but here are some examples commonly used in
Earthships :-
● Tyres
● Bottles
● Cans
● Rammed Earth
● Adobe
● Cob
● Bamboo
● Wood
● Other materials

4 - BUILDING WITH NATURAL & RECYCLED MATERIALS
Overview:
● Tyres - an 'Earthship
Signature' material
● Bottles - full width through
wall to admit light
Tyres: Wikicommons, Eugene Kim
from San Francisco, USA - Tire Bricks
Bottle Wall, AD / Earthship.com.

Overview:
● Aluminium Can Walls,
essentially ‘lost formwork’
● Rammed Earth
Can walls: Victorgrigas, Wikicommons Rammed Earth :- AG Credit Lobby Wall,
RammedEarthWorks.com

Overview:
● Adobe
● Cob
Adobe Brick Wall - 4 Person Eco
Home, Taiwan
Cob Wall :- wikicommons

Overview:
● Bamboo
● Wood
● Other materials - straw / straw
bale, urbanite, engineered
timber beams (glulam timber /
bamboo), paper insulation,
expanded clay - many options
Bamboo, wikicommons, licence. Log, wikipedia

Details: Tyres - an 'Earthship
Signature' material
Tyres: Eugene Kim, Wikicommons Concrete Blocks, wikipedia.
A very common objection to using
tyres, is that ‘they don’t look nice’.
They don’t. But neither do concrete
blocks.
Of course, finishes are applied to
the interior and exterior surfaces of
walls in addition to the ‘structural’
blocks used.
? Issue with offgassing - some say
yes, others say no. Google it.

Tyres - Positives
Tyres: Eugene Kim, Wikicommons
● Readily available
● Cost
● Mass - stored heat
● Size - thick walls (2 ft)
● Almost any dirt will do (in a
form & not a finished surface)
● Amazing engineering
● Flexibility with wall design
● Durability

Bottles - full width through wall to
admit light
Bottle ‘brick’: Jessica Reeder,
wikipedia
Bottle Wall, AD / Earthship.com.
Re-using bottles is similar to using
aluminium cans as formwork, using
glass bottles reduces the amount of
sand/cement required in a wall.
The obvious advantage to using
glass bottles, is that light is admitted
through them, creating some very
pleasing walls. Little energy is
required to repurpose, compared to
melting down to recycle.

Aluminium Can Walls, essentially
‘lost formwork’
Can walls: Victorgrigas, Wikicommons
Re-using aluminium cans is similar to
using glass bottles, reducing the amount
of sand/cement required in a wall.
The aluminium cans form a space in the
wall that then requires no sand/cement.
The wall is a kind of ‘honeycomb’ of
mortar or concrete when finished,
requiring far less material to construct.
The wall is then rendered in a similar way
to any other wall.

Rammed Earth
Rammed Earth :- AG Credit Lobby Wall, RammedEarthWorks.com
My personal favourite ;-). Although not
necessarily the best for everything!
Monolithic
No board / rendering / plastering required
to finish.
As massive as rammed earth in tyres.
Requires formwork very similar to pouring
concrete, so a little more technical.
Beautiful wall finishes.
Easier to mechanically ram earth (see
Minke, small wacker plates / pneumatic
tampers)

Adobe
Sand, Clay.
Rice Straw / Husks / etc
Easy to make
Very pleasant aesthetically
Easy to recycle
Can be (nearly) as massive as a tyre wall
/ rammed earth wall
As with other earth-based materials,
Adobe bricks regulate humidity well
Some reports of difficulty keeping clean Adobe Brick Wall - 4 Person Eco Home, Taiwan

Cob Wall
Soil, straw
Massive - thermal mass
Materials are readily available
Relatively easy to build
Time required between ‘courses’
Freeform / flexibility with wall design
As with tyre walls, rammed earth, adobe,
cob is also fireproof.
Cob Wall :- wikicommons

Other Materials
Straw
Straw bale
Urbanite
Engineered timber beams (glulam
timber / bamboo)
Paper / wool insulation
Expanded clay
….Many options…..

End of Building with Natural &
Recycled Materials
Any Questions?

5 - Water Harvesting

5 - WATER HARVESTING.
here:-
Water Harvesting, Earthship Principle 5

WHY do we want to harvest rainwater in Taiwan?
(or anywhere: UK, US, Europe?)
Before we get into Water Harvesting ‘Earthship Style’:

Morakot (2009): https://visibleearth.nasa.gov/view.php?id=39731
US
We get rain, right?

US
● Taiwan, is the
Rainiest Developed
Country
on the planet.
● The whole planet.

US
Taiwan averages:-
● 2.6 metres of rain
annually.
8.5 feet
102 inches
2600 mm
● Source: wikipedia

US
● Taiwan's heaviest rainfall
in history :-
● 2009 Typhoon Morakot
● Measuring 3.06 metres of
rain in Alishan & Chiayi
● (over 10 feet, or 120
inches), over 2 or 3 days.
● 3+ metres of rain, in 2 or
3 days.
● More climate info: CWB

"Why do we want to retain water in a country like Taiwan where
we measure rainfall in METRES?"
(or the UK, nearly a metre, the US, Europe….etc etc)
So, again, the question:-

Year: 2015
“Taiwan is facing its worst
drought in 67 years, with the
island reservoirs at
dangerously low levels.”
Source: BBC
Droughts & Shortages

Every year, there is the threat
of another water shortage.
Shimen Reservoir at 25%
7th March 2015.
Source: Taiwan News

1st June 2018:
(basically building a higher dam wall...)
“Taipei, June 1 (CNA) To ease the recent shortage of
water in Taiwan, Premier Lai Ching-te (賴清德) declared
Friday that measures will be taken to increase Taiwan's
water supply to 1.9 billion tons by 2031, which means
there will be an increase of 5.2 million tons of water on
average each day.”
Source: Focus Taiwan
18th April 2018
“Water shortage looming in Tainan”
Source: Focus Taiwan
Image: Wushantou Reservoir, June 2018, Taiwan News

Silt now accounts for a third of the capacity at 6
of Taiwan’s 18 main reservoirs.
“Enough silt accumulates in
Taiwan’s reservoirs every year to fill
one Baihe Reservoir (in Tainan) and
every 10 years to fill a Shihmen
Reservoir (in Taoyuan).”
“capacity of reservoirs for storing
water will be down to half of their
designed capacity by 2030”
Source: cw.com.tw
2018 2030
(worst case)
SILT
SILT

We actually get very little rain in:-
● October
● November
● December
● January
In the South - even worse - 90% of rain
falls in the rainy season, May to October
(wikipedia)
No rainy season…..= Problems.
‘Water Rationing’ is already mentioned
many times in the news.

So, we really need to store more water.
That's obvious.
So what do we do with our water when we do get
rain?

● We send it straight down the
drain….
● into the river….
● then out to the ocean.
We cannot easily use that water once it’s in the
river unless we use big dams.
As far as we are concerned, our water is gone
as soon as it goes down that drain.
Then because we need more water….we are
starting to build desalination plants to take it
back out of the oceans….Amcham

5 - WATER HARVESTING / “RETENTION”.
How do we
get….
From This
Video: Brad Lancaster

To This
???

Methods:
Very Simple.
Very cheap.

Brad Lancaster- Tucson Arizona,
U.S.
Rainwater Harvesting at home, spread to the
town.
‘Planting the Rain’

Zach Weiss - Project in the tropics -
….always storing water in the ground wherever they can.
Slowing Water down, Protects against dry AND
drought years…
One thing that struck me, studying permaculture
topics over the last 6 months, is about water
retention.
Swales, dams, ponds, doing everything we can to
slow water down, and soak it into the ground
before it ends up in a river.
This seems to create a lot of life in the soil at
depth, even reinstating springs that might be long
forgotten.
Video: Zach Weiss, Elemental Ecosystems: Youtube Channel | Website

5 - WATER HARVESTING
Water Harvesting with an Earthship is really simple.

We collect all the water we need from > rain on the roof

The rainwater goes from the roof, and through simple particle traps >

If we want to stop leaves from trees, insects etc falling in the water, we simply fit a
Filter / Screen to the top of the gutter (we all use these in Taiwan on Windows)

From the simple Particle Trap, water goes to the Cisterns / Water tanks, usually
buried in the Earth Bank
There is then a WOM (water organising module) in the house that filters & pumps
water to a pressurised tank for washing / bathing / laundry etc.

End of Water Harvesting
Any Questions?

6 - Food Production

6 - FOOD PRODUCTION
here:-
Earthship Principle #6 - Food Production

6 - FOOD PRODUCTION
Things to consider:
● Water
● Nutrients
● Light
● Soil Microbiology & Safety
● Food Producing Plants
● Perishables
● Expensive / Valuable
● Unobtainium

6 - FOOD PRODUCTION
Water
As we have already seen, there is a plentiful
supply of water that plants love in an
Earthship - ‘Greywater’ from hand basins,
showers and baths.
Greywater can be used in the planter along
the full length of your home to grow pretty
much whatever you like within the space
available.
The remaining greywater is captured,
filtered and then used to flush toilets.
Washing machines, showers,
baths, dishwashers can drain
large volumes of water, so
often go to an outside planter.
Handbasins & the kitchen sink
are good candidates for your
inside planter(s)

6 - FOOD PRODUCTION
Nutrients
Dead skin and hair are some of the things
that will be nutrients for some of the
microorganisms in your planter.
Depending on your choice of soap for
washing, and if you are running your
washing machine or dishwasher into a
planter, there might be different levels and
types of nutrients available for your plants.
Certainly some Nitrogen, and Phosphorus
might also be in the mix to a greater or
lesser degree.
Compost & Compost Tea would of course
be something that could be added.

6 - FOOD PRODUCTION
Light
In some designs, part of the roof is also
glazed, to allow more light in for plants, and
also to harvest more heat during the day.
Regular household glazing usually filters UV
light - but if you want maximum plant
growth, greenhouse glass / plastic can also
be used.
If in a hotter climate, more shading may be
preferred, as in this image.
Living in a Tropical / Sub-Tropical region, I
have also considered having no
‘greenhouse’, with the planter outside.

6 - FOOD PRODUCTION
Soil Microbiology
There is research that shows “no significant
difference in contamination levels was
observed between crops irrigated with tap
water, untreated greywater, and treated
greywater.” (see Greywater Safety,
references)
Having already mentioned Compost &
Compost Tea earlier, it is also important to
note that Compost & Compost tea inoculate
your soil with beneficial microorganisms that
then also ‘out-compete’ harmful organisms
such as E.Coli. (see Dr. Elaine Ingham, The
Soil FoodWeb, references)

6 - FOOD PRODUCTION
Food Producing Plants
(From the Earthship Manual)
Start with Hardy Plants
● Grapes
● Aloe
● Geraniums
Then ‘Easy to start’:
● Tomatoes
● Zucchini
● Lettuce
● Peppers
Personal Choices & Thoughts:
● Perishables
● Expensive / Valuable
● Unobtainium ;-)Suggested plants for Indoor
planter(s)

6 - FOOD PRODUCTION
Food Producing Plants
• Beans – mungbean, long beans, green beans, winged
• Peppers – red, yellow & green bell peppers
• Kalamansi lemon
• Chilis – long variety
• Tomatoes
• Watermelon
• Courgettes
• Brassicas
• Arugula spinach
• Chard
• Mizuna
• Daikon
• Purple mustard
• Garlic chives
(thanks to J. Golandez for the suggestions at Daruma Eco-
Farm)
Suggested plants for the
Tropics

6 - FOOD PRODUCTION
Outdoor planters are useful for the higher
volumes of water coming from e.g. the
washing machine, bath etc.
Larger areas, larger plants, shrubs and trees
can be irrigated with this water.
Berries, fruit trees, or whatever grows well
outdoors in your area can benefit.
Root crops - in the Earthship manual Vol 1 -
this is recommended. Greywater Action
don’t recommend it (see references).Outdoor planter(s)

6 - FOOD PRODUCTION
End of Food Production
Any Questions?

Appendix:
Natural Air Conditioning
Using The Earth To Cool (& Dehumidify ?) Air

Appendix (a) - NATURAL AIR CONDITIONING.
Dew Point :
“The dew point is the temperature to which air must be
cooled to become saturated with water vapour. When
further cooled, the airborne water vapor will condense to
form liquid water (dew).”
Think of pouring a cold drink into a glass. As the glass
gets colder, condensation forms on the glass.
This is actually ‘dehumidifying’ the air.

Dew Point :
We don’t need to know the formula for calculating the
Dew Point.
Dew Point changes with (a) Temperature, and (b)
Relative Humidity
The guys at www.dpcalc.org provide us with the Dew
Point Calculator.
Here, we can see at 40℃, for Humidity at 86%, gives us
a Dew Point of 37℃.

So, we know the Dew Point is 37℃.
Using the information from
‘1 - Thermal Heating & Cooling’
We can see that the ground
temperature at a depth of 1 or 2
metres, is often 10℃ to 15℃ cooler
than the ground or ambient
temperature above ground.
Florides, Georgios & Kalogirou, Soteris. (2019). Annual ground temperature
measurements at various depths.

Florides, Georgios & Kalogirou, Soteris. (2019). Annual ground temperature measurements at various depths.
(0m = Ground Temperature)

So:- it makes sense to investigate Natural Air Conditioning &
Dehumidifying, given the weather conditions in Taiwan -
Specifically the temperature difference of Air, and Ground,
and very high Relative Humidity which is common.
If further Air Conditioning were
required, perhaps energy costs could
be reduced by using the natural
temperature of the earth underground.

More Info on ‘Dew Point’ - Wikipedia. Dew Point Calculator - dpcalc.org.
End of Air Conditioning
Any Questions?

In the previous meeting, we
discussed some basics
about Siting, Building
Orientation, and Solar Angles.
You can watch a short video here
if you didn’t attend the meeting.
Appendix: Solar Angle Basics

REFERENCES
Earthship Global - 6 Principles
Appropedia - Earthships
Temperatures Underground - ResearchGate
More Info on Solar Gain - Wikipedia link
Dew Point - Wikipedia link
Dew Point Calculator - Image Permanence Institute
Bamboo for construction - ECHO Technical Notes #92
Greywater Safety - Reuse of Domestic Greywater for the
Irrigation of Food Crops
Open Source Ecology - Earthship
Dr. Elaine Ingham - The Soil FoodWeb

Green Citadels. Explore eco-friendly
earthships with sustainability pioneers
REFERENCES

Earthships 6 principles

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