SWES 210 1st Edition Lecture 28Outline of Last Lecture II. weather vs climateIII. how do GHG’s warm atmospherea. greenhouse effectb. most abundant greenhouse gasc. GHG with most impact on atmIV. Studying past climatesa. Ice coresb. Sediment coresc. Tree ringsd. OtherV. Studying current conditionsVI. Studying future climatea. Climate modelsi. Natural climate changeii. Biological climate changeiii. Anthropogenic b. Trends= the keeling curvec. Future trends= temperature, precipitation, sea levelsOutline of Current Lecture VII. BioenergyVIII. Biomass for electricitya. Biofuelsi. Ethanolii. Advantagesiii. Problemsb. Biodiesalc. Other biofuelsCurrent Lecture- Future impacts ocean circulationo Themohaline circulation depends on differences in temperature and salinity Cool, dense water sinso Addition of freshwater from glacial melting will impact salinity potential turnoff?- Responding to climate trendso Reducing emissionsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. Automobile technology, mass transportationo New energy sources Going solar, nuclear powero Forestryo Policy and Kyoto protocol Carbon taxesBioenergy- renewable- if done sustainably- Bioenergy (biomass energy)= energy obtained from organic material that makes up organismso Wood, charcoal, agricultural crops, manureo All of our energy came from biomass prior to 1850, i.e. burning woodo Bioenergy is in the mix when thinking about our energy challenges Over 1 billion people use wood or heat, cooking and light Overharvesting is a concern: causes deforestation, erosion and desertification- greenbelt movement in Kenya grew from this resource overuse- Biomass for electricity: Bioenergyo Biomass- burn materials to produce heat- run a power planto Biomass power plant, Skelleftea Sweden= a leader in bio energyo Total electricity capacity in US= 1000 GW- Bioenergy= much more significant in fuelso Bio fuels= fuels produces from plants and algaeo What is an advantage of bio fuels over fossil fuels? Renewable source of energy, carbonneutral= plants take in CO2, and when burn release CO2- Questions for today?o What kinds of bio fuels are there? Ethanol from corn, biodesile, o What are they produced from? From crops/ agricultureo Do you use bio fuels? Could use biofules in your car, yes we use them.o What are the cutting edge technologies in bio fuels?- Ethanol as a biofuelo Ethanol produced form sugar (starch and cellulose)o Corn, sugarcane-easy to breakdown, competes with foodo Cellulose= harder to breakdown, no competition with foodo In 2013, 13 billion gallons of ethanol were made in the US from corn to power carso To compare: 134 billion gallons of total gasoline were used in 2013- Cars can run on 100% ethanol- currently care use E10 in Uso Flexible fuel vehicles can run in E-85 85% ethanol, 15% gasoline 8 million cars are in the US Most gas stations do not yet offer this fuel- Brazil leads in ethanol production from sugarcaneo 50% of new brazilian cars are flexible fuel vehicleso pure ethanol ( 100% ethanol is much cheaper than gasoline)- corn based ethanol has some problemso growing corn impacts ecosystems (pesticides, fertilizers, irrigation) and takes up land thatcould be left unfarmedo ethanol competes with food and drives up food priceso as farmers shifted to ethanol, corn for food dropped (30% of corn crop goes to ethanol)o in 2008 rising corn grain prices led to protests in mexicoo cellulosic ethanol is a better alternative- needs more biotech development switchgrass provides fuel now and may provide cellulosic ethanol- cellulosic ethanol fuelso starch vs. cellulose- both contain sugar which can be tuned into ethanolo cellulose requires more energy to break down into sugar components- more difficult toprocess- biodiesal= another biofuelo biodiesal from fats (vegetable oils, cooking grease, palm oil, animal fats or algae for anexample)o vegetable oil gels in cold weather so works better if chemically broken down into individualchainso chains that make up vegetable oil are similar to regular diesalo what is the difference between ethanol vs. biodiesalo can they be interchanged?- Biodiesal powers engineso Vehicles can run on 100% biodiesal (B20= 20% biodiesal)o Biodiesal reduces emissionso Its fuel economy is goodo It costs a little bit more than gasolineo crops are specially grown using land (deforestation)- novel biofuels are being developedo algae produce lipids than can be converted to biodiesel their carbohydrates can be fermented to make ethanolo can be grown in ponds, tanks, or photobioreactoso algae grows fast and can be harvested every few days it can use wastewater, ocean or saline water it can capture CO2 emissions to speed its growtho biofuels from algae are currently expensiveo algae is a candidate for a next-generation biofuel- focus on science: OMEGAo jonathan trent from NASA= studies freshwater and marine microorganismso developed the use of their biochemical’so explored using algae in bas to produce biofuelso system is called