How nature works? The Emergy methodology approach. Some ideas about how to produce Biofuels in Eco-units taking into account nature and society. Enrique Ortega, FEA/Unicamp. Campinas, SP, August 6 th, 2006

Available energy potential Complementary exergies and materials Exergies of different quality Interaction process In nature, the potential energy interact with other available exergies and raw materials to produce resources with higher energy intensity, that constitute the work of the system! The potential energy is used to produce this transformation and a great part of it is degraded to produce the work. The degraded energy is usually referred as “heat”. Exergy Work that flows out of the system Dispersed energy (heat) Recycling (internal flow) System Net exergy produced adding exergies Feedback Production

Available potential energy Complementary energies Better quality energies Interaction Complementary energies Better quality energies Interaction The external exergy captured by the system is transformed into a new resource that has potential energy of a different kind; this product will participate of a sequence of steps of intake and conversion of exergy until all the useful potential is used.

Materials with better exergy Interaction Dispersed materials Recycled materials Raw materials from nature It is external exergy that is transformed within the system that impulses the materials cycle in ecosystems, in human beings, in human economy and in biosphere. Potential energy transferred to other systems Materials recycling Dispersed Energy Interaction Materials with better exergy Exergy of a external diffuse continuous source

The diffuse solar exergy is transformed into vegetal biomass and then used by a net of consumers. At each new stage of the chain the quantity of exergy transferred diminishes. Wastes might have materials with available energy that decomposers can use to grow and as result nutrients (humus) can be returned to initial steps of energy chain. Diffuse Exergy Decomposers Recycling Materials

Main system functions: external source, photosynthesis, stocks of materials, consumers, decomposers, flows. The self-organization develops a hierarchical structure. In this diagram the symbol’s sizes are proportional to mass.

The chain can grow when receiving additional exergy (renewable resources used faster than their recovering time, fossil fuels and minerals that are extracted with these additional resources). Minerals Predatory use of renewable resources Fossil energies Natural carrying capacity Non sustainable carrying capacity

There is a interdependence among the systems components. Form left to right exergy flows to provide support to upper levels of trophic chain; high quality exergy and basic nutrients flows in a countercurrent. The feedback flows changes its quantity and quality when non renewable resources are used. Natural Ecosystems Agricultural ecosystems Urban systems Non renewable resources Renewable resources

Ocean Water in atmosphere Volcanoes Natural landscape and farms Urban systems Raw materials from rural areas Fossil fuels Renewable energy resources New resources Water and environmental services Environmental services Minerals and sediments Industrial products obtained from oil Infra-structure organization Biomass biodiversity Minerals after microbial solubilization Anthropic interaction with Biosphere Direct solar radiation Petroleum, gas, coal

Emergy flows in the nature-society system (Brown & Ulgiati, 2004) Ocean Gases, Sediments, Wastes Solar Emergy Atmosphere Terrestrial crust Civilization Intense heat Gravitation force of Moon and Sun Earth internal heat Flows expressed in E24 sej/year 3,93 3,84 8,06 34,3 External emergy: 15,8 Hydrocarbons: 26,1 Nuclear: 2,9 Wood and soil: 2,8 Minerals: 2,5 Non renewable resources Total emergy: 50,1 Materials Minerals Minerals and other stocks

Solar radiation Gravitation force from Sun and Moon Earth deep heat P1P1 P2P2 P3P3 Material stocks Interactions Product flow Basic raw minerals Transformity = Emergy _______________________________________ Product exergy Transformity = 1 ________________________ Efficiency Product exergy _____________________________________ Total emergy used Efficiency =

Biosphere emergy (Y) can be assumed constant. As the product mass (P i ) and its energy content (E p ) decreases along the chain, the transformity (Tr) grows along the network. Transformity = Emergy used Product exergy Y P1P1 P2P2 P3P3 The transformity reveals the hierarchical position of each resource in the different networks of the Universe. As more scarce or concentrated it is the resource becomes more valuable due to its interaction power. Tr = Y E Pi Y = cost of exergy used, in terms of solar emergy

Transformity of rain water Tr = Emergy/Exergy = Y / E Y = Earth total emergy flow = 15,83 E24 sej/year Rain water total flow = 1,04 E17 kg/year Tr = Y/E = 15,83 E24 sej/year / 5,19 E20 J/year And so on … Tr = 3,1 E4 sej/J Gibbs Free Energy of rain water = 5 E3 J/kg E = Rain water exergy = 5,19 E20 J/year

External energy resources in order of intensity and renewability Transformity of resource produced

Procedure for emergy calculation: 4.Express the flow in solar emergy terms (seJ or seJ/area/time). 1.Show the flow J 2 in its usual units; 3.Multiply by corresponding transformity (Tr); 2.Convert the usual units to International Systems units (SI);

Aggregation and comparison of flows on the same basis

Resumed diagram Indicators Efficiency: Tr = Y/Ep Net emergy: EYR = Y/F Investment: EIR = F/I Renewability: %R = 100(R/Y)

Label of energy performance for certification purposes

Ecosystem processing of emissions, effluents and solid wastes. Control of local and global temperature, atmosphere quality maintenance, genetic vigor preservation. Rural products Bio-diversity and biomass People at the cities knowledge, democratic control Spare time leisure, medicinal herbs, ecologic culture Polinization, top soil production and preservation, flooding control, percolated clean water, top water biological filtration. Minerals and oil Industrial products Polluted water Food, wood, and textile fibers Natural ecosystems Agro- ecosystems Environmental services and biomass fuel production Biofuels Energy Emissions, effluents and solid wastes.

Individual farms or parcels: low intensity subsystems with production destined to self- consumption (subsistence) or regional market (with low productivity) Very reduced area for natural ecosystems and practically no environmental services Model 1: individual small land areas

Monoculture plantation concentrates land ownership, decreases manpower in rural area and produces several kinds of erosion: top soil, native vegetation, genetic reserves, human culture. Natural ecosystems reduced to a minimum. Model 2: plantation Fertilizers, Pesticides, Herbicides, Machinery, Fossil fuel. Agri-business: Additional services: negative externalities. Hidden subsidy Commodities

Local industry Integrated system: Native forest, Agro-forestry, Individual parcels, Animal husbandry, Biomass energy; Industry; Recycling, Waste treatment. Model 3: Eco-unit Native vegetation Agro- forestry Energy crops Grain, grass, shrubs Cattle Individual parcel People Biomass energy Food, meat Waste recovery

Micro-distillery, local and regional agro- industry Eco-unit: micro-distillery Native vegetation Agro- forestry Energy crops Grass, grains, shrubs. Cattle Individual parcel People Energy Native forest products Water, top soil, biodiversity, local climate Agro-forestry products Individual parcels products Self-consumption Recycling: vinasse, ash, manure Waste use Food (meat)

Micro-distillery, local agro-industry and regional industry Native vegetation Eucalypt Sugar cane Grasses, grains, shrubs Cattle Individual parcel People Ethanol (94%) Manure Environmental products and services Water, soil, biodiversity, local climate Vegetable garden products Family consumption Vinasse Young bulls (meat) Sun, wind, rain. Soil minerals Atmospheric nitrogen Ash, fiber Lean calves Wood poles (posts) Pesticide for ants Other materials & energy Public services External manpower Eco-unit: Fazenda Jardim, Mateus Leme, MG, Brazil Urea Regional biodiversity and water resources Efficiency: Tr = Y/Ep Net emergy: EYR = Y/F Investment: EIR = F/I Renewability: %R = 100(R/Y) Indices:

Fazenda Jardim, Mateus Leme, MG, Brazil Transformity: Tr = Y/Ep = seJ/J Net emergy: EYR = Y/F = 3.1 Investment: EIR = F/I = 0.47 Renewability: %R = 100(R/Y) = 66% Indices: Pictures and results