03. Intro

1. Solar Power: photovoltaic, concentrated solar power, solar heat.

2. Wind Power: Wind turbines

3. Hydroelectric Energy: hydropower, wave/tidal

4. Bioenergy: biofuels, biogas, biomass.

5. Geothermal Energy: heat, steam.

1. Steam Turbine: Steam turbines use high-pressure steam to turn the blades of a turbine and generate electricity. This steam is created by heating water to a very high temperature. The source of the heat can vary, including burning coal, nuclear reactions, or capturing geothermal energy. à High efficiency at large scale.

2. Gas Turbine: In a gas turbine, pressurized gas is used to spin the turbine. This gas can be created by burning natural gas, propane, diesel fuel, or other types of fuel. Gas turbines are typically used in peaking power plants, which are small, flexible plants that can be turned on quickly to meet sudden increases in demand. In summary, the main differences can be noted threefold: the type of fuel they use (gas versus steam), the way they generate power (through combustion versus heat conversion), and their respective efficiency and scalability.

A combined cycle power plant is a type of power station that combines the processes used in both the gas turbine and steam turbine systems to produce electricity. It works as follows: 1. The Gas Turbine Cycle: The initial stage is similar to a conventional gas turbine plant. A gas (like natural gas) is combusted, and the energy from this combustion is used to drive a turbine which in turn generates electricity. 2. The Steam Turbine Cycle: A combined cycle power plant uses the waste heat from the gas turbine to produce steam. 3. Using the Steam: This steam is then used to drive a steam turbine. à By coupling these processes together, a combined cycle power plant can reach efficiencies of over 60%, much higher than the individual efficiencies of either the gas turbine or steam turbine process alone.

1. Coal, Oil, Natural gas, Uranium à Steam Turbine à Electricity 2. Natural gas, Oil à Gas Turbine à Electricity 3. Sunlight à PV panels à Electricity

The function of n/p (n-type/p-type) doping in silicon for Photovoltaic (PV) cells is to create a p n junction, which is essential for their operation. Doping the silicon material allows for the creation of an electric field, necessary for generating an electric current. p-Type Doping: When silicon is doped with a material like boron (which has three valence electrons), a "hole" is created in the silicon structure. These holes can accept an electron, making them positively charged, hence the name "p-type" silicon. n-Type Doping: If silicon is doped with a material like phosphorus (five valence electrons), an extra electron is added to the lattice structure. It is weakly bound and easily free to move, creating a negatively charged "n-type" silicon. The p-n Junction: When these two types of material (n-type and p-type) come into contact, they create a p-n junction. This junction creates an internal electric field. When sunlight (composed of particles called photons) hits the solar cell, it can provide eno

Monocrystalline Silicon PV Cells:

• single crystal structure of silicon • the most efficient PV cells, with efficiencies often over 20% • more expensive

Polycrystalline Silicon PV Cells:

• multiple small silicon crystals • less efficient, efficiencies around 15-17% • more cost-effective

Thin-Film PV Cells:

• one or more thin layers of photovoltaic material on a substrate • less efficient (generally around 10-12% efficiency) • cheaper to produce and have a more versatile use due to their flexibility

Concentrated solar power (CSP) plants generate electricity by using mirrors or lenses to focus a large area of sunlight, or solar thermal energy, onto a small area. The concentrated light is then used as a heat source for a conventional power plant.

1. Large mirror arrays track the sun and adjust their angles to reflect sunlight onto a small receiver. Depending on the facility's design, this could be a tower, a series of tubes, or a parabolic trough.

2. The receiver collects and absorbs the concentrated sunlight, converting it into intense heat. In most CSP systems, this heat is used to heat a fluid (like a molten salt or synthetic oil), creating a hot liquid or steam.

3. This heated fluid is then used to generate steam that drives a turbine connected to an electricity generator. The mechanical energy generated by the turbine is converted into electrical energy by the generator. à In some cases, the heated fluid can be stored and used to produce electricity even when the sun isn't shining (for example, at night or on cloudy days).

1. Parabolic Trough Systems: They use parabolic mirrors to concentrate sunlight onto a receiver tube filled with heat-absorbing liquid (like oil).

2. Linear Fresnel Reflector Systems: This type of CSP system uses a series of flat, or slightly bent, mirrors to focus sunlight onto a fixed receiver located at a certain height above the ground.

3. Dish/Engine Systems: In these systems, a parabolic dish of mirrors focuses the sunlight onto a receiver located at the focal point of the dish.

4. Power Tower Systems: Also known as 'central receiver systems', they involve a large field of mirrors (heliostats) which individually track the sun and focus the solar energy onto a single receiver mounted on top of a central tower.

The nominal output of a photovoltaic (PV) cell, also known as rated power, can be defined as the highest power output under specific environmental conditions like a certain temperature and light intensity (usually 25°C and 1000W/m² sunlight).

Can the output be higher than the nominal power? Generally, the answer is no. The nominal power is determined under specific "Standard Test Conditions" (STC), which are generally ideal and often more favorable than normal outdoor conditions. However, in certain conditions (i.e. lower temperature but higher light intensity), the output might exceed the rated power for a short period, although this is not common. Meanwhile, the actual output in real-world conditions is usually lower than the nominal output due to factors such as the angle of the sun, dust and pollution, and temperature effects on the PV efficiency.

1. Wind à Wind Turbine à Electricity

2. Geothermal à Steam Turbine à Electricity

3. Sunlight à PV panels à Electricity

Advantage: Reduced Maintenance Costs: By eliminating the gearbox, direct-drive turbines can significantly reduce maintenance costs and downtime. Gearboxes are prone to mechanical wear and tear and can be costly to fix or replace.

Disadvantage: Size and Weight: Direct-drive wind turbines need larger and heavier generators to operate at lower speeds, which can increase the weight of the nacelle and the cost of the turbine tower and foundation. This weight increase can make the transportation and installation of the turbine more challenging and expensive.

Flexibilization of biogas plants refers to modifying the operational characteristics of these facilities to allow them to better adapt to the fluctuations in the electrical grid. This can involve adjusting the amount of biogas produced – or storing it – to match supply with periods of high energy demand or low energy production from other sources (like wind or solar).

It can be achieved through various methods: 1. Power-to-Gas Technology: This involves converting excess electricity (from wind or solar sources) into hydrogen through electrolysis, which can then be mixed with the raw biogas to produce biomethane, a highly efficient gas that can be stored and used when required. 2. Storage of Biogas/Biomethane: By storing excess biogas or biomethane, you can use it to produce energy during periods of high demand or low supply. 3. Co-digestion: Introducing new feedstock or co-substrates can increase the gas yield and make the production process more flexible.

Large amounts of land are required to grow biomass crops, which can create competition with food crops and contribute to deforestation. à Biomass energy is often considered carbon neutral, the burning of biomass (like wood pellets or agricultural waste) does release carbon dioxide, as well as other pollutants such as particulates, which can contribute to air quality problems.

Enhanced Geothermal Systems (EGS): Traditional geothermal systems require naturally occurring pockets of steam or hot water underground. EGS, on the other hand, is a new technology that creates these conditions artificially, meaning geothermal energy could be harnessed almost anywhere.

Short-term Energy Storage: Lithium-Ion Batteries. Medium-term Energy Storage: Flow Batteries Long-term Energy Storage: Pumped Hydroelectric Storage, power-to-gas technologies (H2).

• Cost Comparison Calculation • Profit Comparison Calculation • Profitability Comparison Calculation • Amortization calculation

The Levelized Cost of Electricity (LCOE) is a measure used to compare the cost-efficiency of different electricity production methods. à Lifetime costs divided by energy production

• The initial cost of investment expenditures (Cinv) in € or $ • Maintenance and operations expenditures (Cfix) in € or $ • Fuel expenditures (if applicable) (Cvar) in € or $ • The total output of the power-generating asset will include: o The sum of all electricity generated (E) in kWh • The last two important factors to be considered in the equation are: o The discount rate of the project (i) in % o The lifetime of the system (n) in years

• Increased lifetime • Increased interest rate • Increased full load hours?

Increased Lifetime: The longer the power plant's life, the more electricity it will produce over its lifetime, which helps spread the initial capital and maintenance costs over a greater amount of produced electricity. à decrease in the LCOE. Increased Interest Rate: The interest rate represents the cost of capital or the rate of return required by the project investors. A higher interest rate increases the cost of capital à increase in LCOE. Increased Full-Load Hours: The more full-load hours, the more energy produced. Just like with increased lifetime, more full-load hours will spread the fixed costs over more units of electricity à decrease in LCOE.