Human Passive Energy Systems – Temperature Control
If energy, resources and environment are depleting then what are the passive energy systems that Humans can use to survive up to 2050.
This is the analysis that covers the passive energy system of Temperature.
Earth Environment Conditions
The planet varies its temperature by day and night by being exposed or hidden from the energy of the sun.
The hottest ever recorded daytime temperature on Earth was 56.6 deg C / 134 deg F
Source: http://www.ncdc.noaa.gov/news/month-climate-history-earth%E2%80%99s-hottest-temperature
The coldest ever recorded night-time temperature on Earth was −89.2 deg C / −129 deg F
Source: http://en.wikipedia.org/wiki/Oymyakon
Human Basic Survival Need
Humans can survive a day on Earth if temperatures are to low or to high.
Human beings follow the Earth pattern and vary their own temperature during day and night.
If the temperature varies over a minimal range then human beings cannot survive.
Over a smaller range their internal chemical systems begin to fail.
The average human body temperature is 37°C (98.6°F)
Below 9 deg C the risk of hypothermia increases
Between 9 to 12 deg C the likely hood of a stroke increases
Between 12 to 16 deg C the likely hood of respiratory disease increases
Between 16 to 18 deg C they become uncomfortable
Between 18 to 21 deg C they are comfortable
Between 21 to 24 deg C they become uncomfortable
Above 24 deg C the likely hood of a stroke increases
At 24–26 deg C / 75.2–78.8 deg F the likely hood of death increases
At 44 deg C / 111.2 deg F death occurs.
Human Evolved Temperature control system.
Humans have evolved passive temperature control systems to regulate their body temperature.
Humans can increase their exposed surface area, stand up, to increase heat loss by convection with air or water.
Humans have hair over their bodies that increases surface area to increase heat loss by convection.
Humans can decrease their exposed surface area, crouch, to decrease heat loss by convection and increase heat transfer to all areas by conduction.
Humans have hair over their bodies that can when overlapped and made denser decrease heat loss by convection and increase heat transfer to all areas by conduction.
Human Passive Energy Input Gain – Radiate Heat - Sun
The potential solar energy available at the surface of the Earth
Source: Wikipedia and Smil (2006)
= 122,082,699,137,591 kw
= 122082699137591000 w
This potential energy source is spread over the whole surface area of Earth
= 150,000,000 km2
Allowing for the change from day to night the potential energy source is spread over
= 75,000,000 km2
= 75000000000000 m2
Allowing for a the whole potential energy source over this area
= 122082699137591000 / 75000000000000 m2
Which gives an energy level available to be collected
= 1,628 w /m2/day
The first Passive Energy Gain for humans is therefore. = 1628 w /m2/day
Humans can gain an average solar irradiance of 250 w/m2 from the sun each day on the Earth by being in the correct location to be exposed to the suns radiant heat energy.
This can be accomplished without any technology, including clothes.
Source: http://en.wikipedia.org/wiki/Insolation
The second Passive Energy gain for humans is therefore = 250 w/m2
The rate of transfer of this energy is controlled by the human activity level.
The units this energy is expressed in are MET units.
1 MET = 58.2 w/m2
Source: Cornell University Ergonomics Web DEA3500: Ambient Environment: Thermal Conditions
This gives the human internal energy transfer system in comparison with the environmental energy input a ratio of 250 w/m2 from the sun each day in radiated energy to approx. 58w/m2/day internal human metabolic rate. An approximation of 4 w/m2 environmental to 1 human w/m2.
Applying this to the human outer layer; the skin; as the interface with the environment then the energy interface potential can be calculated.
Total area of human skin organ = 1.8m2
Total environmental interface energy = 1.8 x 250 = 450 w/m2 / day
Total human interface energy = 1.8 x 58 = 105 w/m2 / day
The third Passive Energy gain for humans is therefore = 105 w/m2/day
In varying their activity the humans can control this energy reservoir and its distribution for their own use.
When reclining humans would use 0.8 MET = 0.8 x 58= 47 w/m2/day
When seated quietly humans use 1 MET = 1 x 58 = 58 w/m2/day
When working in an office humans use 1.2 MET = 1.2 x 58 = 70 w/m2/day
When standing but relaxed humans use 1.2 MET = 1.2 x 58 = 70 w/m2/day
When carrying out light activity humans use 1.6 MET = 1.6 x 58 = 93 w/m2/day
When carrying out medium activity humans use 2 MET = 2 x 58 = 116 w/m2/day
When carrying out heavy activity humans use 3 MET = 3 x 58 = 174 w/m2/day
Source: Cornell University Ergonomics Web DEA3500: Ambient Environment: Thermal Conditions
Human Passive Energy Input Gain – Chemical Energy – Food and Water
Humans can also generate heat internally by consuming carbohydrates, proteins, roughage, minerals, vitamins and fats. The energy produced from the consumption and reduction in density of these natural products produces chemical that can be transported via. the blood stream to parts of the human body to repair and reactivate it.
If the average human is taken as 1.8m high, 68 kg, age 50 and male then this gives a Basal Metabolic Rate reading BMR of 1575
If the average human is taken as 1.8m high, 68 kg, age 50 and female then this gives a body mass reading of 1411
BMR x activity = total daily energy expenditure in calories.
As with the radiant heat input humans can control this energy reservoir and its distribution for their own use.
Male
no activity = 1.2 x 1575 =1890 calories per day
light activity 1 to 3 days a week = 1.4 x 1575 = 2205 calories per day
moderate activity 3 to 5 days a week = 1.6 x 1575 = 2520 calories per day
hard activity 6 to 7 days a week = 1.7 x 1575 = 2678 calories per day
very hard activity 7 days a week = 1.9 x 1575 = 2993 calories per day
Female
no activity = 1.2 x 1411 = 1693 calories per day
light activity 1 to 3 days a week = 1.4 x 1411 = 1975 calories per day
moderate activity 3 to 5 days a week = 1.6 x 1411 = 2258 calories per day
hard activity 6 to 7 days a week = 1.7 x 1411 = 2399 calories per day
very hard activity 7 days a week = 1.9 x 1411 = 2681 calories per day
Taking the moderate levels in each of the sexes the average for a human would be
2520 + 2258 / 2 = 2389 calories per day
Allowing 1 calories per 4.18400 joules
2389 x 4.1868 = approx 10002 joules per day
This allows for 1 person to radiate approx.
3 wh/day over 1.8m2 = approx 5 wh/day
The fourth Passive Energy gain for humans is therefore = 5 wh/m2/day
Combined Human Environment, Internal and Radiated Energy Potential
The previous calculations can be added together to give a potential passive energy total.
Total Potential Passive Energy gain for humans = 1988 wh/m2/day
= 725,620 wh/m2/year
This amount of passive energy when compared to that of a post 2020, peak oil, 2storey 3 Bedroom 4 Person House of approx. 87m2 that would have to achieve 87 x 30 kWh/m²/yr , 2610 kwh/yr to comply with EU low energy house standards indicates that the human passive energy input to this energy requirement could be as high as 725,620 wh/m2/year, 725 kwh/m2/year of the energy need enough to allow survival without additional technology being involved.
Source: EU low energy house standards.
Human Technology Need
Humans have a very tenuous energy link to the environment chemical factory of the Earth.
Humans can survive a day on Earth if temperatures are to low or to high.
Humans can survive four to six weeks without eating.
Food, when consumed, takes 2 to 3 days to pass through a human being completely and outputs energy during all of this time.
Source: http://en.wikipedia.org/wiki/Digestion#Human_digestion_process
The passive energy systems to assist in temperature control are therefore enough to allow survival without additional technology being involved.
The human being however has to migrate to utilize these passive energy systems and in doing so they loose the energy obtained.
Therefore any new technology proposals must reduce the migration need for the human beings. The Architecture of their dwellings must include passive solar and passive food storage systems.
Ian K Whittaker
Website:
https://sites.google.com/site/architecturearticles
Email: iankwhittaker@gmail.com
10/11/2013
12/11/2013
14/10/2020
1465 words over 4 pages