Bioenergy

Question 1

What is biomass?

Answer 1

Everything biological, but for energy purpose forests, lantations, agriculture crops and restflows from forestry, agriculture and society

Question 2

What is modern bioenergy?

Answer 2

Electricity & combined heat and power (biomass, MSW, biogas)
Heat in buildings (biomass, biogas)
Transport (crops, ag by products, biogas)

Question 3

Can biomass be seen as a carbon neutral energy source?

Answer 3

Yes if three conditions fulfilled
1. Balance bw new balance and harvestation
2. Input energy streams need to be CO2 neutral (fuels for trucks, machines, boilers)
3. Handle the land so carbon is not released from the soil

Question 4

Controversies of biofuels

Answer 4

• uses a lot of land (release carbon in soil, destruct rainforests)
• increase food price
• significant eco & env impacts (hypoxia in rivers & oceans, loss of biodiversity)

Question 5

What is payback time?

Answer 5

Time to repay the land-use carbon debt (yrs), to even out

T_payback = C_LU / C_sav

LU = land use, sav = saved