Methane from Biomass Methane makes up 85% of the natural gas extracted from the ground. In the presence of water and absence of oxygen, organic material will ferment naturally. Such organic materials include: Crops Agricultural waste (animal or vegetable) Waste from lumber mills waste from breweries Algae Sludge from sewage treatment plants Municipal waste Fermentation by bacteria in the absence of oxygen is called anaerobic fermentation

Methane from Biomass Same heating value as natural gas High conversion efficiency(50-70% of the useful energy is converted) High cost Useful in systems that can generate their own power - for example sewage plants

Biodiesel Diesel fuel made from vegetable oil, recycled cooking grease or oil and animal fat Used as a fuel additive, designate the same way we designate ethanol fuels-i.e B# where # is the amount of biodiesel in the diesel fuel. B20 widely used in trucks and school buses

Nuclear Energy Nuclear Fission - the splitting of two atoms Nuclear fusion – the combining of 2 atoms Both process release energy

Atomic structure Atoms are composed of protons , neutrons and electrons – discovered in the 1930’s Protons – positively charged q=1.602176487×10−19 C m=1.67262158 × 10-27 kg Neutrons – no charge m=1.6749 x 10-27 kg Electron –negative charge q =−1.602176487×10−19 C m= 9.10938215×10-31 kg

Atomic structure Protons and neutrons make up the nucleus Electrons orbit the nucleus at specific distances known as energy levels Atomic number = number of protons=Z Atomic mass number = A = Z+ N, where N is the number of neutrons Atomic mass = total mass the electrons, protons and neutrons Atomic weight = the ratio of the average mass of an atoms 1/12 of the mass of an atom of carbon-12. Ion –if an atom loses or gains an electron and has a net charge Isotope-atom has the same number of protons but different number of neutrons

Atomic Structure Atoms are held together by forces There are four forces in nature Gravity -force between masses Electrostatic forces-like charges repel unlike charges attract Strong nuclear force - causes an attraction between protons and neutrons Weak nuclear force – causes protons to transform into neutrons and neutrons in to protons

Atomic Structure In atoms, the electrostatic force is holding the electrons to the nucleus, since the electrons are negatively charged and the protons are positively charged. The protons in the nucleus are being pushed apart by the electrostatic force since they have the same charge, but the strong nuclear force overcomes this repulsion on the atomic size scales and holds the protons together.

Fission In the late 1930s, it was discovered that if a uranium nucleus was bombarded by neutrons, it absorbed the neutron and became an unstable isotope of uranium, which then spilt into 2 separate atoms (Krypton and Barium) and emitted more neutrons and gamma rays

Is mass conserved? Now the mass of the fission products plus the excess neutron should equal the mass of the initial incident neutron and the uranium. But it doesn’t. Where did the mass go? Well, remember E = mc2 - mass cannot be created or destroyed, only converted to and from energy, so the missing mass must be converted into energy.

How much energy 200 MeV is released per fission event The fission of 1 g of uranium or plutonium per day liberates about 1 MW. This is the energy equivalent of 3 tons of coal or about 600 gallons of fuel oil per day No CO2 emissions! Vastly superior in terms of energy per amount of fuel

Self sustaining or chain reaction The fission reaction itself releases neutrons, these can be used to fission additional nuclei, so the elements are there for a sustained or chain reaction. Tremendous power capability made this an ideal weapon.