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Biomassa energie Voor deze vorm van energie wordt afval gerecycled. Door vergisting van mest en houtafval onstaat biogas. Ook verbranding is een mogelijkheid. 15 procent van de wereld energie wordt al op deze manier opgewekt. Een voordeel is echter dat je in crisistijd altijd biogas kunt produren en dat je een goede manier hebt om afval te recyclen. Biodiesel uit algen
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Geothermische energieontstaat door het benutten van de warmte van de aarde. Hoe dieper je in de aarde gaat hoe warmer het wordt. Aardwarmte is een onuitputtelijke bron en vraagt weinig onderhoud. In Nederland wordt het systeem toegepast in de tuinbouw.
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Getijden energie van oceanenEen getijdencentrale vangt door middel van turbines energie op uit het veranderen van eb in vloed en andersom.
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Kernenergiekan extreem veel energie opwekken. Het
voordeel van deze energiebron is dat
hij niet erg duur is en dat hij veel energie
oplevert. |
Waterkrachtwordt vaak in bergachtige gebieden
toegepast. Doordat een rivier waterkracht
ondervind zal hij naar beneden lopen en zo
in de waterkrachtcentrale de turbines in
beweging zetten. Stuwmeren zorgen voor het
verzamelen van voldoende water om de
turbines aan te drijven.
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Zonne-energiezal de meest waarschijnlijke vervanger
worden van de fossiele brandstoffen. Het kan
op grote schaal verzameld worden, in Amerika
zijn er al hectares vol met zonnepanelen die
energie omzetten.
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NIEUWE ONTWIKKELINGEN: Ethanol-making bacteria
Ethanol-making bacteria eats what we can’t
Sept. 9, 2008
A team of researchers from Dartmouth's
Thayer School of Engineering and Mascoma
Corporation in Lebanon, N.H., have made a
discovery that is important for producing
large quantities of cellulosic ethanol, a
leading candidate for a sustainable and
secure alternative to petroleum-derived
transportation fuel. For the first time, the
group has genetically engineered a
thermophilic bacterium, meaning it's able to
grow at high temperatures, and this new
microorganism makes ethanol as the only
product of its fermentation.
The study was published online this week in
the journal Proceedings of the National
Academy of Science.
"Our discovery is one potential avenue for
research to facilitate turning inedible
cellulosic biomass, including wood, grass,
and various waste materials, into ethanol,"
says Lee Lynd, the Paul E. and Joan H.
Queneau Distinguished Professor in
Environmental Engineering Design at the
Thayer School of Engineering at Dartmouth.
"In the near term, the thermophilic
bacterium we have developed is advantageous,
because costly cellulase enzymes typically
used for ethanol production can be augmented
with the less expensive, genetically
engineered new organism."
Lynd explains that this discovery is only
the first step, a proof of concept, for
future development of ethanol-producing
microbes that can make ethanol from
cellulosic biomass without adding enzymes.
Lynd is the corresponding author on the
study and the chief scientific officer and
co-founder of Mascoma Corp., a company
working to develop processes to make
cellulosic ethanol.
All of the ethanol currently used in this
country as an additive to gasoline comes
from corn. However, it is widely recognized
that cellulosic biomass has significant
advantages over corn as a raw material for
ethanol production, provided that a
cost-effective technology for converting
cellulosic materials can be developed.
There are several features that make
cellulosic ethanol attractive. The raw
material, cellulosic biomass, is available
on a large scale, does not include food
crops, and is cost-competitive with
petroleum on both an energy and a mass
basis. The technology to convert cellulosic
biomass to ethanol is steadily improving,
and it also has the potential to be
cost-competitive with gasoline production.
Environmental benefits include a sustainable
carbon cycle with near-zero net greenhouse
gas emissions, because the carbon dioxide
captured growing the biomass roughly equals
what is emitted while running an engine. In
addition, ethanol has excellent performance
and compatibility with existing internal
combustion engines as well as fuel
cell-powered vehicles of the future.
Innovative technology for ethanol production
from cellulosic raw materials has been a
central focus of Lynd's, who won the
inaugural Lemelson-MIT Sustainability Award
in 2007, a top honor for inventors.
Opm.: wereldwijd is er veel onderzoek naar bovengenoemde directe omzetting van cellulosevezels in ethanol.