19/4 - Energycrop in sw Flashcards
Why (not) bioenergy-systems?
1 Biomass production for energy has low land-use efficiency and interferes negatively with the production of other commodities such as food and fibre,
2 Biomass production for energy is resource-use inefficient and thereby compromises sustainable development and finally,
3 Biomass is too expensive and not competitive with fossil fuels.
Drivers for bioenergy development
- The main drivers for pushing biomass production efficiency are the needs to bring down costs to make biomass more competitive with fossil fuels and to be able to compete with other means of land use.
- Other drivers include social and environmental concerns, such as greenhouse gas emissions (climate!), diminished availability of water, nutrients and biodiversity.
- Nutrient use efficiency, water use efficiency and land-use efficiency consequently all are important measures for efficiency assessments of sustainable biomass production systems.
Key factors; production
The major determinants of biomass production per unit area consist of:
- The environment (soil and climate), crop management (modification of environment by means of tillage, irrigation and fertilization) and
- genetic constitution of the plant material.
Pests and diseases påverkan på biomassa
• Pathogens and predators also may lead to either a decreased biomass production or consumption of biomass, thereby decreasing the real or apparent light-use efficiency of the system.
Breeding/ genetics - mål
- Main plant breeding goals are targeted towards minimising production losses by pests and towards allocation patterns which render high proportions of harvestable (above-ground) biomass.
- When the aim of the growing system is to yield specific plant components, such as plant oil rather than overall biomass, breeding and genetics are employed to change within-plant resource allocation accordingly
ideal SRC
1) has a minimal difference between gross and net productivity and
2) allocates a maximum of its resources to easily harvestable plant parts.
grow as fast as possible with most of the biomass going above ground
and as much of the energy from the sun to go to the biomass and not
to fight pests
Crops in agroforestry exempel
- Willow (Salix) - harvest every 3 år
- Poplar - harvest every 20år
- Hybrid aspen - harvest every 20år
Annually harvested crops exempel
combust
• Reed canary grass
• Hemp
ethanol
• Wheat, triticale
biodisel
• rape seed
Vad är REM
(biodiesel)
rape seed
energi från rape?
varför inte varför
- well established crop
- standard machinery
- RME (biodiesel)
- food production often more profitable
- RME production based on imports
- crop rotation limitations
Cereals for fuel ethanol
varför varför inte
- well established crops (winter wheat & triticale)
- standard machinery
- conflict food / energy production
- if cereal prices are high: food production is more profitable
- crop rotation limitations
Cereals for combustion
varför varför inte
- well established crops (mostly oat, some triticale and rye)
- standard machinery
- large-scale: cereals not competitive with wood fuels
- if cereal prices are high: food production is more profitable
- local solutions in small- and medium scale
varför varför inte salix
• recently established crop • special machinery available • reluctance to cultivate salix due to.. …special machinery …low income …long-term investment (20-30 years) …interference with water drainage systems etc.
harvest during winter is good due to the leafs falling off and giving back nutrients
to the ground, the stumps of the willow will regrow over and over again
Hemp for combustion
varför varför inte
- crop in trials / small-scale production
- (modified) standard machinery
- cultivation for local market (as pellets)
- large-scale bale production not yet competitive
Reed canary grass for combustion
varför varför inte
- crop in trials / small-scale production
- (modified) standard machinery
- problems with high ash content
- high emissions (SOx, NOx)
- co-combusted with e.g. wood fuels, peat etc.
works well with the northern part of Sweden
works well if you want an open landscape.
What are the demands on an energy crop from the farmers/growers?
Can grow on bad soil, cost efficient , stable market, high yield, long term investment, nutrient/ water efficient, diversification, good income, flexibility, biodiversity
What are the demands on an energy crop from the society?
Landscape issues, environmental friendly, cheap energy, low risk (stable supply), not smelly
The salix cropping system
the shoot needs time to grow roots
weed control is extremely important
otherwise the weeds will outcompete the willow
0) ta bort ogräs
1) plant a part of a shoots
from a 1 year old
2) grows for 4 years
before harvet
3) repeat for ca 20-30 years
before re-harvest
Smidigaste sättet at harvest småträd?
different harvest technics is used
but they all cut the stem, most efficient
way is to gut it into wood ships and drive
them directly to the burning-center.
but you can make them into bails
Bad är problemet med förutsättningar med hur mycket man kommer få?
Verkligheten ger ofta mycket mindre än vad men förutspåpga missade faktorer
Varför svårt att investera i detta?
Would you invest if you knew that:
• You will get your first income 5 years from now.
• The prerequisites for your investment will have changed after 5 years. Subsidies will have increased, decreased or maybe are taken away completely.
• The economy for your salix plantation is not better than for other crops during the first and second harvest, 9 years from now. Thereafter you will earn a lot of money if the development of the market is good and the crop grows well.
NON-TECHNICAL BARRIERS:
- Market
- Attitudes and advisory work
- Policy
- Research and Development (Soc-Econ)
- Public acceptance
Lessons learned
- Drivers for developing and implementing a new biomass crop change through time
- Need for breeding programs that continue to provide the market with new material
- Stand design and management has to be adapted to the performance of new clones
- Site choice, preparation and successful establishment crucial for later production
- Large-scale implementation needs to be well prepared in advance
- Extension work needed to support farmers
- Grant scemes should be targeted towards production, not towards planting……
- Planting SRF implies a long-lasting commitment for farmers and thereby for all actors in the chain
- Design your multi-purpose systems to adress a variety of markets
- During large scale implementation, commercial fields need to become the main research and development objects
- SRF is an international discipline that needs to be developed further by means of international co-operation
Summary
Development of bioenergy production is strongly dependend on
• Raw material prices
• EU and national bioenergy policies / commitment
Established energy crops – production is limited by
• Crop rotation problems (oilseed rape, cereals)
• Low biomass demand of district heating plants (combustion technology)
• Non-competitive production costs
New energy crops – production is limited by
• Insufficient knowledge (production, handling)
• Insufficient market structures
Possible scenarios
• Import of cheap biomass for energy and domestic production of food
• Import of food and domestic production of cheap bioenergy
