the algae house - · PDF filehydrogen produced by the algae necessitated its housing in some...
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the algae house - algaetecture Karuga Koinange - Chris Bowler - Daniela Krug In collaboration with Cambridge Researchers & Engineers algae?! Algae is fast becoming the preferred source of bio-mass for use in the production of bio-diesel. Unlike conventional means of processing biomass crops however, a far cleaner, greener method is possible by way of hydrogen production. In the absence of sulphur they will switch from the production otf oxygen as in normal photosynthesis, to the production of hydrogen. Capture of hydrogen, used in conjunction with a fuel cell, opens up the potential for a totally CO2 free route to end-use consumption of energy. The team set out to investigate the potential for the micro-generation of algae within a domestic context through a process of experimental design. urban-rural algaetecture why tubed algae? ...energy flows What are the benefits of cultivating algae in a closed-system, closely integegrated with the architectural form of a house, as opposed to a natural pond based open system? The geometries and solar system developed in AlgaeHouse are adaptable to an increased urban density and scale. Retractable privacy blind Structural column Louvre support cable Roof construction: zinc compressed insulation boarding timber structure High performance UV triple glazing Insulation & Damp proof membrane Adjustable ventillation opening reflective pool White painted surface coating drainage cover waste water & biomass under floor heating Algae tubes Hydrogen Nutrients (sewage) Recycled Water Carbon dioxide Algae solution Louvre system the algae house From early on in the design development it became clear that certain environmental constraints on successful cultivation were analogous to those required by humans. Specifically, these concerned issues to do with light and heat. Like people, algae thrive on exposure to high levels of solar insolation. However, the capture of gaseous hydrogen produced by the algae necessitated its housing in some form of sealed, transparent tank. Such tanks are highly prone to over-heating, killing the algae if rising to a temperature much above 30ºC. It became clear therefore that there existed the potential for the algae and domestic spaces of our ‘Algae House’ to enter a symbiotic relationship, whereby the one promoted the optimum environmental conditions for the other and vice versa. (This close relationship is even evident in the waste water recycling system whereby filtered brown water provides vital nutrients for the algae to grow). The form of the façade was developed to achieve maximum solar insulation from the sun, whilst maintaining a stable temperature, so optimising the production of hydrogen. Through careful consideration of the algae tubes’ altitude and azimuth orientation to the sun, and working in combination with a fixed louvre system, direct solar heat gain is allowed only during winter months and on spring and autumn mornings and evenings. The shallow pool of water, or ‘moat’, located adjacent to the façade is intended to perform two functions. Firstly, the pool reflects low angle sun up to the overhanging algae façade, whilst absorbing more of the higher energy high angle mid-day summer sun. Secondly, as the major component of heat energy is transferred in the infrared band of the spectrum of light, the water usefully absorbs much of the heat from direct sunlight before reflecting it up to the algae. Calculating an estimate for the total amount of energy produced through the AlgaeHouse system was achieved through consultation with algae biochemical engineer and Cambridge PhD candidate Ben Taylor. Through this collaboration a tripartite energy extraction strategy was identified as realising the optimal potential from the algae. Indeed, algae are in fact unable to produce hydrogen for sustained periods of time and so, in the AlgaeHouse system, energy is also released through the extraction of lipids (oils) and bio-gas (through the processing of algae bio-mass in an anaerobic digester). To convert these oils and gas to useful electricity, rather than utilising the traditional ‘dirty’ technology of conversion through combustion, instead a catalytic-reactor based fuel processor converts the oils to hydrogen. This hydrogen, combined with that produced directly from the algae, is converted to electricity and heat in a hydrogen fuel cell. Based on the assumption that current trends in the genetic modification of algae continue towards the anticipated level of 15% efficiency in the conversion of light energy to hydrogen and given a volume of 2545 litres of algae solution, the house is estimated to produce 4100kWh per annum – enough to cover all energy demands of the occupants. Algae and people may not present themselves as obvious bedfellows, but through this project we hope to have shown that the integration of algae as an energy generator within a house is not only feasible, but that co-habitation can result in a self-sustainable symbiotic system and open up many exciting architectural possibilities for ‘green living’.in Algae Photo- bio-reactor A total of 4059 kWh/ annum produced by the Algae facade + SUPPLY - DEMAND Breakdown of energy Hydrogen or Biodiesel Car Fuel Processor Electric Appliances Underfloor Heating Fuel Cell Biomass Algae Anaerobic Digester Algae Oil Press Biodiesel Biogas Electricity Electricity Hydrogen Waste Heat from Fuel Cell Waste Heat from Fuel Cell Hydrogen Cool climate Algae strain used; Chlamydomonas f-9 Marine (saltwater) tolerant 100 dwellings per hectare = approx. 300000 kWh per annum per hectare ‘AlgaeTower’ ‘AlgaeCourtyard’ Hot, arid climate Algae Strain used; Scenedesmus obliquus Tolerant of hot, arid conditions 25 dwellings per hectare = approx. 65000 kWh per annum per hectare ‘AlgaeHouse’ Moderate climate Algae strain used; Chlamydomonas reinhardtii Favour moderate conditions 6 dwellings per hectare = approx. 24600 kWh per an- num per hectare summer summer winter winter ratio of sides heat loss/ gain in kWh /day +12 +6 -6 0 -12 1:5 1:3 1:1 1:1.6 Optimal 3:1 5:1 [Academic use only] Optimal summer summer winter winter ratio of sides heat loss/ gain in kWh /day +12 +6 -6 0 -12 1:5 1:3 1:1 3:1 5:1 1:1.3 [Academic use only] summer winter ratio of sides heat loss/ gain in kWh /day +12 +6 -6 0 -12 1:5 1:3 1:1.1 3:1 5:1 Optimal [Academic use only] Space heating 20% Computer control 4% Bio-reactor pumps 14% Heat recovery ventilation fan 0.5% TV 3% Washing machine 2% Lighting 13% Laptop 1% Fridge/ freezer 5% Kettle 2% Gas oven 6% Hot water 2% Showers 28% Hydrogen 11% Biogas from anaerobic digestion 43% Algal biodiesel 46%
Transcript of the algae house - · PDF filehydrogen produced by the algae necessitated its housing in some...
the
alga
e ho
use
- alg
aete
ctur
e K
arug
a K
oina
nge
- Chr
is B
owle
r - D
anie
la K
rug
In c
olla
bora
tion
with
Cam
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Eng
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algae?! Algae is fast becoming the preferred source of bio-mass for use in the production of bio-diesel. Unlike conventional means of processing biomass crops however, a far cleaner, greener method is possible by way of hydrogen production. In the absence of sulphur they will switch from the production otf oxygen as in normal photosynthesis, to the production of hydrogen. Capture of hydrogen, used in conjunction with a fuel cell, opens up the potential for a totally CO2 free route to end-use consumption of energy.
The team set out to investigate the potential for the micro-generation of algae within a domestic context through a process of experimental design.
urban-rural algaetecture
why tubed algae?
...energy flows
What are the benefits of cultivating algae in a closed-system, closely integegrated with the architectural form of a house, as opposed to a natural pond based open system?
The geometries and solar system developed in AlgaeHouse are adaptable to an increased urban density and scale.
Retractable privacy blind
Structural column
Louvre support cable
Roof construction:zinccompressed insulationboardingtimber structure
High performance UV triple glazing
Insulation &Damp proof membrane
Adjustable ventillationopening
reflective pool
White painted surface coating
drainage cover
waste water &biomass
under floor heating
Algae tubes
Hydrogen
Nutrients (sewage)Recycled WaterCarbon dioxideAlgae solution
Louvre system
the algae house From early on in the design development it became clear that certain environmental constraints on successful cultivation were analogous to those required by humans. Specifically, these concerned issues to do with light and heat. Like people, algae thrive on exposure to high levels of solar insolation. However, the capture of gaseous hydrogen produced by the algae necessitated its housing in some form of sealed, transparent tank. Such tanks are highly prone to over-heating, killing the algae if rising to a temperature much above 30ºC. It became clear therefore
that there existed the potential for the algae and domestic spaces of our ‘Algae House’ to enter a symbiotic relationship, whereby the one promoted the optimum environmental conditions for the other and vice versa. (This close relationship is even evident in the waste water recycling system whereby filtered brown water provides vital nutrients for the algae to grow). The form of the façade was developed to achieve maximum solar insulation from the sun, whilst maintaining a stable temperature, so optimising the production of hydrogen. Through careful consideration of the algae tubes’ altitude and azimuth orientation to the sun, and working in combination with a fixed louvre system, direct solar heat gain is allowed only during winter months and on spring and autumn mornings and evenings. The shallow pool of water, or ‘moat’, located adjacent to the façade is intended to perform two functions. Firstly, the pool reflects low angle sun up to the overhanging algae façade, whilst absorbing more of the higher energy high angle mid-day summer sun. Secondly, as the major component of heat energy is transferred in the infrared band of the spectrum of light, the water usefully absorbs much of the heat from direct sunlight before reflecting it up to the algae. Calculating an estimate for the total amount of energy produced through the AlgaeHouse system was achieved through consultation with algae biochemical engineer and Cambridge PhD candidate Ben Taylor. Through this collaboration a tripartite energy extraction strategy was identified as realising the optimal potential from the algae. Indeed, algae are in fact unable to produce hydrogen for sustained periods of time and so, in the AlgaeHouse system, energy is also released through the extraction of lipids (oils) and bio-gas (through the processing of algae bio-mass in an anaerobic digester). To convert these oils and gas to useful electricity, rather than utilising the traditional ‘dirty’ technology of conversion through combustion, instead a catalytic-reactor based fuel processor converts the oils to hydrogen. This hydrogen, combined with that produced directly from the algae, is converted to electricity and heat in a hydrogen fuel cell. Based on the assumption that current trends in the genetic modification of algae continue towards the anticipated level of 15% efficiency in the conversion of light energy to hydrogen and given a volume of 2545 litres of algae solution, the house is estimated to produce 4100kWh per annum – enough to cover all energy demands of the occupants.
Algae and people may not present themselves as obvious bedfellows, but through this project we hope to have shown that the integration of algae as an energy generator within a house is not only feasible, but that co-habitation can result in a self-sustainable symbiotic system and open up many exciting architectural possibilities for ‘green living’.in
Algae Photo-bio-reactor
A total of 4059 kWh/ annum produced by the Algae facade
+ SUPPLY - DEMAND
Breakdown of energy
Hydrogen or Biodiesel Car
Fuel Processor
Electric Appliances
Underfloor Heating
Fuel Cell
Biomass
Algae
Anaerobic Digester
Algae OilPress
Biodiesel
Biogas
Electricity
Electricity
Hydrogen
Waste Heat from Fuel Cell
Waste Heat from Fuel Cell
Hydrogen
Cool climate
Algae strain used;
Chlamydomonas f-9Marine (saltwater) tolerant
100 dwellings per hectare
= approx. 300000 kWh per annum per hectare
‘AlgaeTower’
‘AlgaeCourtyard’
Hot, arid climate
Algae Strain used;
Scenedesmus obliquusTolerant of hot, arid conditions
25 dwellings per hectare
= approx. 65000 kWh per annum per hectare
‘AlgaeHouse’
Moderate climate
Algae strain used;
Chlamydomonas reinhardtiiFavour moderate conditions
6 dwellings per hectare
= approx. 24600 kWh per an-num per hectare
summer
winter
ratio of sides
+40+20
-200
-40
1:51:31:13:15:1
summersummer
winterwinter
ratio of sides
heat loss/ gain in kWh /day
+12
+6
-6
0
-12
1:51:31:11:1.6
Optimal
Optimal
3:15:1
summersummerwinterwinter
ratio of sides
heat loss/ gain in kWh /day
+12
+6
-6
0
-12
1:51:31:13:15:1 1:1.3
[Academic use only]
summer
winter
ratio of sides
+40+20
-200
-40
1:51:31:13:15:1
summersummer
winterwinter
ratio of sides
heat loss/ gain in kWh /day
+12
+6
-6
0
-12
1:51:31:11:1.6
Optimal
Optimal
3:15:1
summersummerwinterwinter
ratio of sides
heat loss/ gain in kWh /day
+12
+6
-6
0
-12
1:51:31:13:15:1 1:1.3
[Academic use only]
[Academic use only]
summer
winter
ratio of sides
heat loss/ gain in kWh /day
+12
+6
-6
0
-12
1:51:31:1.13:15:1
Optimal
[Academic use only]
Space heating 20%
Computer control4%
Bio-reactor pumps14%
Heat recovery ventilation fan
0.5%TV3% Washing
machine2%
Lighting 13%
Laptop 1%
Fridge/ freezer5%
Kettle 2%
Gas oven 6%
Hot water2%
Showers28%
Hydrogen11%
Biogas from anaerobic digestion
43%
Algal biodiesel46%
Algae TubesWC
Lipid extraction press
Fuel processor
Anaerobic digester
Fuel Cell
Inverter/ transformer
House Power Sensors
Appliances
Control Computer
Filtration System
Algae Remnants Nutrients
CO2
biodiesel
biomass
hydrogen
hydrogen
(hydrogen car)
hydrogen store
nutrient water
nutrient water & algae remnants
biomass
space heating
pumps and valves not shown
biogas
mains water
mains water
hot water
electricity
air
air
brown water
Credits:
Ben Taylor (Cambridge University, Department of Chemical Engineering & Biotechnology)Phd researcher specialising in Algae based energy sources.
Ben Sheppard (Cambridge University, Department of Engineering)David Valinsky (Cambridge University, Department of Architecture)Oliver Hudson (Cambridge University, Department of Engineering)
integrated algaetecture
the algae house - algaetecture Karuga Koinange - Chris Bowler - Daniela Krug
In collaboration with Cambridge Researchers & Engineers
Mitigating solar energyThe physical properties of water have been utilised in the design of AlgaeHouse and play a fundemental part in mitigating the strength of solar radiation reaching the algae tubes.
High angle, summer sun; Mitigation of sunlight desirable. As the incident angle of light becomes steeper, a higher proportion passes below the surface of the water. As it passes through infra-red heat energy is absorbed. The reflective coating on the floor of the pool reflects the reduced energy light back up to the algae tubes.
Low angle, winter sun; Maximum solar insolation desirable. As the incident angle of light becomes shallower, a higher proportion of light is reflected off the surface of the water.
[Academic use only] [Academic use only]
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
1.5
0.5
1.0
0
500250 1000 1500 2000 2500
Wavelength (nm)
Solar Radiation vs Water Absorption Spectrum
Surface Reflectivity of Water
Visable InfraredUV
Spe
ctra
l Irr
adia
nce
(W/m
2 /nm
)S
pect
ral I
rrad
ianc
e (W
/m2 /n
m)
Abs
orpp
tion
co-e
ffici
ent o
f Wat
erA
bsor
pptio
n co
-effi
cien
t of W
ater
0.1
00 10 20 30 40 50 60 70 80 90
Ref
lect
ivity
Incident Angle From Normal, Deg
Approximately 50% of total solar radiation energy is absorbed in the heat carrying infra-red waveband by the water pool.
The physical properties of water have been utilised in the design of AlgaeHouse and play a fundemental part in mitigating the strength of solar radiation reaching the algae tubes.
High angle, summer sun;Mitigation of sunlight desirable.As the incident angle of light becomes steeper, a higher proportion passes below the surface of the water. As it passes through infra-red heat energy is absorbed. The reflective coating on the floor of the pool reflects the reduced energy light back up to the algae tubes.
Low angle, winter sun;Maximum solar insolation desirable.As the incident angle of light becomes shallower, a higher proportion of light is reflected off the surface of the water.
Mitigating solar energy
[Academic use only] [Academic use only]
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
1.5
0.5
1.0
0
500250 1000 1500 2000 2500
Wavelength (nm)
Solar Radiation vs Water Absorption Spectrum
Surface Reflectivity of Water
Visable InfraredUV
Spe
ctra
l Irr
adia
nce
(W/m
2 /nm
)S
pect
ral I
rrad
ianc
e (W
/m2 /n
m)
Abs
orpp
tion
co-e
ffici
ent o
f Wat
erA
bsor
pptio
n co
-effi
cien
t of W
ater
0.1
00 10 20 30 40 50 60 70 80 90
Ref
lect
ivity
Incident Angle From Normal, Deg
Approximately 50% of total solar radiation energy is absorbed in the heat carrying infra-red waveband by the water pool.
The physical properties of water have been utilised in the design of AlgaeHouse and play a fundemental part in mitigating the strength of solar radiation reaching the algae tubes.
High angle, summer sun;Mitigation of sunlight desirable.As the incident angle of light becomes steeper, a higher proportion passes below the surface of the water. As it passes through infra-red heat energy is absorbed. The reflective coating on the floor of the pool reflects the reduced energy light back up to the algae tubes.
Low angle, winter sun;Maximum solar insolation desirable.As the incident angle of light becomes shallower, a higher proportion of light is reflected off the surface of the water.
Mitigating solar energy
winter sun
summer sun
equinox sun
bedroom
...closing the
biological cycle.
Algae microscopic reproductionprocess...
Sunpath diagramCambridge, UK
Lat: 51°31’12”N
kitchen area
reflection pool
louvre line (above)
work area
living area
ALGAE
HUMANS
CO2
O2
kWh RECYCLE
Fossil Fuel Power PlantPollution
Waste H20Cleaner H20
WasteLandfill
Pollution
Other benefits to using this system include natural scrubbing of CO2 emissions from household systems and household wastewater treat-ment using renewable algae.
Continuous production system for the generation of hydrogen and biomass from algae
Algae reproduce by cell division. The flow rate within the system is such that the algal cell count
doubles before it reaches the filter. Then half of the algae are
removed while the remainder are recycled, along with the water,
back into the growth system.
The concentrated algal biomass can be processed to extract
the lipids for transformation to biodiesel, with the remaining dry
algal mass fed to an anaerobic digester for production of biogas
for household water heating. The solids from the digester unit can then be used as plant fertiliser, animal feed, or as feed for the
algae.
Algae initially release clean oxygen as they grow in size and number.
Once sulphur is depleted algae produce hydrogen instead of oxygen.
After hydrogen production algae are fed more sulphur to encourage lipid and biomass growth.
Sulphur-limited nutrients from pre-treated wastewater and CO2 from
anaerobic digester
Concentrated algae biomass
Some algae +
most water recycled
Direction of flow
Tangential flow filter
