There is a huge number of possible applications of renewable energy sources. This chapter therefore presents a clear and comprehensive arrangement of the various options to provide a basis for the following steps of the country analysis.
RE can be categorised according to different criteria:
- Form of provision (electricity, heat/cooling, fuel)
- Energy source (solar, wind, water, biomass, biogas, geothermal)
- Site of application (central/decentralised and on-grid/stand-alone system respectively)
- Type of application (application as hybrid power station, application in combined heat (cooling) and power)
- Sector of application (residential, commercial, industry, power, transport) - Plant size (small, medium, large)
The following two matrices (Table 4.3 and Table 4.4) classify RE from two different points of view: In the first case a supply-oriented top-down approach, in the second case a demand-oriented bottom-up approach that is based on the needs to be satisfied. This two-track approach has been chosen to ensure that all technology options can be categorised and no potential field of application is left out.
Based on the three forms of provision - electricity, heat/cooling and fuel - the supply-oriented classifies different renewable energy sources top-down. The main energy sources (e.g. solid biomass) are differentiated into sub-groups (e.g. wooden and agricultural residues, energy crops), which are then further differentiated into resources (e.g. wooden residues from forestry / industry) and technologies respectively (e.g. Dish-Stirling, parabolic trough in the case of the sub-group solar-thermal power generation).
4. Development of a General Technology Matrix to Categorise Renewable Energy Technologies
In the case of solar heat generation, the field of application is also stated, because – different from most of the other technologies – this technology normally is matched with the specific application (e.g. solar cooking, hot water generation, heating etc.). The further columns of state in which sector the technology is located typically, whether it is compatible with CH(C)P and/or hybrid applications,10 if it is normally designed as a stand-alone or as an on-grid system and the scale of its power output. In the column
“Energy Benchmarks resp. Energy Potential”, specific country characteristics (e.g.
median solar radiation of 1 000 kWh per m2 and year) as well as absolute potential within the respective country (e.g. biomass potential of 10 TWh per year) can be indicated. The column “CO2 Reduction Potential” notes whether the climate protection effects of the individual technologies predominantly result from the substitution of fossil energy sources (baseline, see last column of table), from the destruction of Green House Gases (GHG Destruction), or from a combination of both respectively. In the last block of the top-down table, specific properties as well as non-technical implications and co-benefits of the technologies considered can be entered. This includes both quantifiable economic aspects (specific investment costs resp. specific electricity, heating and fuel costs) and ecological, socio-economic and further aspects that can only be indicated qualitatively as exemplified in Table 8.1 (from BMU 2004) which are relevant in this context are summarised in Table 4.2.
The last column of is reserved for country-specific observations and specifies the main competing conventional technology11 that would be replaced by the application of renewable energies (important for the determination of the baseline). This indication is particularly important for CDM projects in order to be able to assess the CO2 abatement potential.
10 CH(C)P refers to combined heat (cooling) and power generation, i.e. combined and therefore more efficient generation of power and heat (and where applicable also cooling) within one process.
“Hybrid systems” are energy generating units (e.g. PV-Diesel or PV-Wind) that are composed of different renewable and fossil energy sources, which by their combination clearly improve the availability (and hence often also the profitability) of the system.
11 Fossil energy sources and non-sustainable use of biomass.
Table 4.1 Exemplary Catalogue of Criteria for the Assessment of the Sustainability of Energy Systems
Criterion Indicator
Climate protection Specific emission of greenhouse gases per kWh Specific emission of air pollutants per kWh Saving of Resources Consumption of non-renewable energy Ecological
aspects
Protection against noise Noise emissions
General interest Potential for economic development Cultural compatibility
Degree of supply equity Degree of participation Socio-
economic aspects
Individual interests Employment effects Health / sanitary effects
Low costs and prices Specific investment costs per kW Cost of generating electricity per kWh
Repairs and maintenance Requirements on specialists and procurement of spare parts
Economic independence Degree of import dependency and regional self-supply
Security of supply / availability Economic
aspects
Potential for the future Degree of know-how development
The above remarks on the top-down are generally valid for all three fields, electricity, heat and fuel. However, in the fuel matrix, instead of the sector of application (residential, industry, power) the type of fuel generation (thermal-chemical / physical-chemical / biophysical-chemical / electrical) is entered. Moreover, the matrix gives cost indications in Euro per kilowatt hour, per mega joule and per litre of fuel respectively.
At this stage, the top-down has been completed in a rudimental and exemplary manner only. While some points can be assessed in general, most have to be assessed by country (e.g. potential, implications), which will take place in the following chapters.
The second, demand-oriented matrix (Table 4.4), by contrast, starts bottom up from the development needs and infers the technologies that are most adequate for meeting these needs. Such a need can for instance be the desire for lighting, to communicate or the desire for cooling of rooms and food. The table first presents the needs that can be met through the application of electricity (sum = 5), second the needs that can be met through the application of electricity or heat/cooling (sum = 3), third the needs that can
4. Development of a General Technology Matrix to Categorise Renewable Energy Technologies
be met through the application of heat/cooling only (sum = 4), and finally the needs that can be met through the application of fuels (development need mobility, sum = 1). Just as in , the bottom-up matrix also presents the general applicability of the technology for CH(C)P and hybrid applications. In addition, the power output and potential for integration in the grid or in stand-alone systems is noted. The last column again notes the competing technologies (baseline) that can be replaced by the application of renewable energies.
In contrast to top-down, the bottom-up Table 4.4 is already fully completed since it is rather universally applicably and does not depend that much on local conditions.
In addition to the application-oriented bottom-up table, Figure 4.1 presents an overview of stand-alone renewable energy systems. This includes direct applications (small power output), which supply only a single unit with power, small-scale networks supplying clusters of buildings, commercial facilities as well as small village network (medium to large power output).
Radio LampBattery charger ...
Miniature application
Water pump (wind powered) Water pump (solar powered) Direct Actuation
wind-powered Direct Heating Direct applications
Solar home systems Wind home systems Hybrid systemes Home Systems
Desalination Purification Water treatment
S c h o o l s Hospitals
Agriculture Operations
Systems for buildings Village network Small-scale networks
STAND-ALONE SYSTEMS
Figure 4.1 Classification and Power Output of Stand-alone Systems
10 W 100 W 1 KW 10 KW 100 KW 1 MW 10 MW
Range of Performance
Table 4.2 Guidelines for a Sustainable Energy Supply
Equality of access: Equal opportunities in accessing energy resources and energy services shall be assured for all.
Protection of resources: The different energy resources shall be maintained for the generations to follow, or there shall be comparable options created to provide sufficient energy services for future generations.
Compatibility with environment, climate and health:
The adaptability and the ability for regeneration of natural systems (the
“environment”) may not be exceeded by energy-related emissions and waste.
Risks for human health – by e.g. an accumulation of problematical pollutants and harmful substances – shall be avoided.
Social compatibility: It shall be assured when realising the energy supply systems that all people affected by the system are able to participate in the decision-making processes. The ability of economic players and communities to act and shape may not be restricted by the systems being set up, but rather shall be
expanded wherever possible.
Low risk and error tolerance:
Unavoidable risks and hazards arising from the generation and use of energy shall be minimised and limited in their propagation in space and time. Human errors, improper handling, wilful damage, and incorrect use shall also be taken into consideration in the assessment.
Comprehensive economic efficiency:
Energy services shall – in relation to other costs in the economy and of consumption – be made available at acceptable costs. The criterion of
“acceptability” refers, on the one hand, to specific costs arising in
conjunction with the generation and use of the energy and, on the other hand, to the overall economic costs while taking the external ecological and social costs into consideration as well.
Availability and security of supply:
The energy required to satisfy the human needs must be available according to the demand and in sufficient quantities, in terms of both time and location.
The energy supply must be adequately diversified so as to be able to react to crises and to have sufficient margins for the future and room to expand as required. Efficient and flexible supply systems harmonising efficiently with existing population structures shall be created and maintained.
International co-operation:
Developing the energy systems shall reduce or eliminate potential conflicts between states due to a shortage of resources and also promote the peaceful co-existence of states by a joint use of capabilities and potential.
Source: BMU (2004)
Table 4.3: Supply-Side Technology Matrix (Top-down Table)
CO2-Red.- Implications & Co-Benefits4)
Energy Source Sector CompatibilitySystem Power Potential Economy Ecology3) Social Further Baseline
Main Group Subgroup
Ressources / Technologies
(Examples) Application Residential Industry/Business Power Sector CHP 5)Hybrid On-Grid Standalone Small Medium Large
Energy Benchmark resp.
Energy potentials [TWh] Energy Substitution GHG-Destruction
Spec.
Invest Costs [!/kW]
Spec. Energy Costs [!/kWh]
economy
Qualification Spare Parts Participation
...
(only relevant for country
specific analysis!)
Biomass1)
(Co-firing)
Residues (Wood)
Wood residues from forestry Wood residues from industry (incl. sawdust)
x
Residues (agricultural) Straw x
Energy crops (renewable raw material)
Short-rotation
plantations x
Biogas1) Residues (Wood)
Wood residues from forestry Wood residues from industry (incl. sawdust)
x
Residues (organic) Bagasse, coconut
shells, rice husk x
Biological waste (Municipal solid wate)
Power generation Cooking
x x
Sludge gas Power generation x x
Landfill gas Power generation x x
Residues (agricultural) Crop residues (incl. gras)
Manure slurry x x
Zoo mass x x
Energy crops (renewable raw material)
Grain, starchy plants, wood from short-rotation plantations Coal Bed Methane1)
Solar1) Solar stove
Solar drying Warm water Heating Process heat Process cooling
Geothermal1) Near surface (heat pump) x x x x
Hydrothermal x x x x x x
HDR technology 6) x x x x
Hydro large (> 10 MW) Storage, run-of-river small (< 10 MW) Storage, run-of-river micro (< 100 kW) run-of-river Wind large (> 100 kW)
small (< 100 kW)
Solar1) PV x x
Solar thermal Dish-Stirling x x
Parabolic trough x
Solar tower x
Solar chimney
Energy Type
Biomass:
x TWh (if applicable broader
differentiated) resp.:
y kWh per qmcultivation
and year
Biogas:
x TWh (if applicable broader
differentiated) resp.:
y kWh per tdry matter
and year
H E A T
2 Implications & Co-Benefits
Production System Potential Economy Ecology3) Social Further Baseline
Main Group Subgroup
Ressources / Technologies
(Examples) thermal-chem. phys.-chem. biochemical electrical On-Grid Stand alone
Energy Benchmark resp.
Energy potentials
[TWh] Energy Substitution GHG- Destruction Spec. Fuel costs [!/kWh] resp.
[!/MJ]
Spec. Fuel costs
[!/l]
economy
Qualification Spare Parts Participation
...
(only relevant for country
specific analysis!)
Liquid Vegetable oil Rape, sunflower,
Jatropha, palm oil etc. x x
Bio diesel (FAME 2)) see above
x x
Bio ethanol Starchy plants (Maize, grain, potatoes)
x x
Sugar plants (Sugar beet, sugar cane)
x x
Bio methanol from Biogas x x
BTL (Fischer-Tropsch) from Biogas x x
Gaseous Hydrogen Wind, solar, biomass x (x) x x x
Bio methan (= Biogas) Biomass x x x x
Note
1)in principle applicable for combined heat and power generation
2)FAME: Fatty Acid Methyl Ester, among RME (Rape Methyl Ester)
3)e.g. acidification potential, Eutrophication Potential, Ozone Depletion Potential and ozone-forming potential, toxicity
4)s.a. under "Guidelines for a sustainable power supply" named aspects
5)e.g. Diesel/PV- or Wind/PV-Systeme
6)HDR: Hot Dry Rock
7)OTEC: Ocean Thermal Energy Conversion
Further technologies / options:
- Solar architecture - Sea water desalination
F U E L SEnergy type
Table 4.4: Application-Orientated Technology Matrix (Bottom-up Table)
Energy type Energy source Aptitude System Capacity Baseline
Development
Need Example Sector
Typical stand alone energy
services
Electricity Heat / Cold Fuel Solar (PV) Solar (Collector) Solar (CSP) Hydro Wind Biomass (solid) Biogas Firedamp Geothermal CHP(C) hybrid 1) Mains Stand alone small medium large
Main Competing Fossil Technology
resp.
Non-Sustainable Biomass Utilisation Access to Electricity Grid Electricity utility,
IPP X X X X X X X X X X X X X Fossil electricity mix
Illumination
Residential
5 h/d with 20 W per household
X X X X X X X Kerosene lamp, wax
candle Entertainment &
Information
Radio, TV, Music
Residential
5 h/d with 5-30 W per household
X X X X X X X Batteries, Diesel
generator Communication Telephone, Fax, Mobile
Phone
Residential
2 h/d with 10-20 W per household
X X X X X X X Batteries, Diesel
generator Freshwater Conveyance &
Irrigation
Fountain water, river
water Residential,
Agriculture
ca. 5 litres/day per household
X X X X X X X Diesel pump
Freshwater Production Sea water desalination (Evaporation / reverse osmosis), water treatment
Residential, Waterworks 24 h/d
X X X X X X X X X X
Drinking water transport per tank lorry, fossil based sea water desalination
Cooling Air conditioning
(absorption cooling, free
cooling) Residential,
Commercial 24 h/d
X X X X X X X X
Electr. compressor air conditioning (Fossil power)
Cooling units for food, medicine...
Medicine, gastronomy, residential 24 h/d
X X X X X X X X X see above
Heating Residential heating
Residential X X X X X X X X X X Gas, oil,Non-sustain. biomass
Warm water
X X X X X X X X X X see above
Cooking Residential,
Commerical (canteen kitchen)
X X X X X X X LPG,Non-sustain. biomass
Commercial & Industrial
Process Heating & Cooling Industry &
Commercial
X X X X X X X X X X X Non-sustain. biomass
Mobility X X X X X X Diesel, petrol
Note: Abb.:
1) e.g. Diesel/PV- or Wind/PV-Systems CSP: Concentrating Solar Power GHG: Greenhouse Gas
RE: Renewable Energies IPP: Independent Power Producer
DL: Developing countries CHP(C): Cogeneration of Heat, Power (and Cold)