Bioenergy & Hydropower

Question 1

Ethanol production in L/ha

Answer 1

Biomass yield * Energy of biomass * efficiency of process / energy of ethanol

[tDM/ha/yr] * [GJ/tDM] / [GJ/m3 / L/m3]

Obs!! If energy of ethanol is in GJ/m3 convert to Liters by dividing!!

Question 2

Emissions from cultivation

Answer 2

Energy requirement for cultivation * Carbon Content / Ethanol per ha

[GJ/ha] * [gC/MJ] / [L/ha] = gC/L

Question 3

Emissions from Cultivation

Answer 3

Energy requirement for cultivation * carbon content / ethanol per ha

[GJ/ha] * 10^3 (matcha MJ) * 20 [gC/MJ] / [L/ha]

Question 4

Emissions from ethanol production(biomass residue + oil)

Answer 4

Production energy * (1-Share of biomass residue energy) * carbon content

[GJ/m3 / 1000 L/m3] * 10^3 (GJ to MJ) * [gC/MJ]

Question 5

Emissions from transport (oil)

Answer 5

Energy for transport * carbon content

[GJ/m3 / 1000L/m3] * 10^3 * [gC/MJ]

Carbon content from oil here

Question 6

Total emissions per Liter ethanol

Answer 6

Emissions from (cultivation + production + transport)

This have been calculated in different steps.

Question 7

Conversion of emissions / L to emissions/km

Answer 7

Emissions / km = emissions / L * Fuel economy

[gC/L] * [L/km] * 44/12 [gCO2/ gC]

Question 8

Carbon neutral system

Answer 8

Original energy production/ha - primary energy / ha = [GJ/ha]

Biomass yield * energy of biomass * conversion efficiency - (total emissions in gC/L / Carbon intensity in gC/MJ ) * ethanol production in L/ha

[tDM/ha] * [GJ/tDM] - [gC/L / gC/MJ] * [GJ/ha]

Question 9

Hydropower eq

Answer 9

P = eta * rho * Q * g * H

Question 10

Potential energy

Answer 10

E = rho * g * (H-D/2) * V

Question 11

Stored potential energy in the part of the dam allierad to be emptied

Answer 11

E=rho * g * (H- deltaDlim/2) * V * deltaDlim/D