Biomass GEM assumptions

Erwan Hemery

12 May 2009

Existing assumptions

Name Capacity (MW)

FOF( %)

Implied maximum

energy (GWh)

Location Heatrate (GJ/GWh)

Variable O&M, $/MWh

Fixed O&M, $/kW

Capital cost, $/kW

Earliest commissioning year

BioCog1 30 30 184.0 Kawerau 12000 10 60 2800 2014

BioCog2 30 30 184.0 Central 12000 10 60 2850 2015

BioCog3 30 30 184.0 Whirinaki 12000 10 60 2800 2016

BioCog4 30 30 184.0 Kinleith 12000 10 60 2900 2030

BioCog5 30 30 184.0 Ashley 12000 10 60 2800 2020

Total: 150 MW

Flow chartTotal biomass resource (PJ)

Biomass for electricity

generation (PJ)

Net energy for electricity

generation (PJ)

Net energy for electricity

generation (GWh)

Required installed capacity (MW)

Losses and own use due to

transformation (PJ)

Direct use energy (PJ)

Start

DUS – Direct Use Share (%)E – Efficiency (%)CF – Capacity Factor (%)

x (1 - DUS)

x (1-E)

x DUS

x E

x 277

÷ (8.760 x CF)

The parameters that were randomly selected are the:• biomass resource available in New Zealand; • share of the energy production used as direct heat;• efficiency of the plant; and• capacity factor of the plant.

MC simulation

How the maximum installed capacity has been derived from the estimated total biomass resource

MC assumptionsNew Zealand Biomass resource• 2008 biomass resources is in the order of 47 PJ;• 83 PJ per annum (pa) in 2030 and 90PJ pa in 2050 will be available

(Scion); • Derating factor to account to the proportion which is technically and

economically available leading to 67 and 72 PJ pa; • Biomass resource range between 67 and 90 PJ.

Share to direct heat• In 2007, around 23 % of the total biomass energy production was

consumed by the electricity generation sector;• The share of energy used for electricity generation could be

anywhere between 23 and 33 %.

Plant efficiency• In the energy data file biomass efficiency of 30 %;• In the future, the plants efficiency will improve as new technologies

become available;• Efficiencies ranging from 30 to 40 %.

Capacity factor• The Kinleith power station over the last couple has averaged a

capacity factor of 0.78;• Capacity factor ranging from 0.7 and 0.8.

Installed capacity

0 100 200 300 400 500 6000

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04P

roba

bilit

y

MW0 100 200 300 400 500 600

0

0.01

0.02

0.03

0.04

0.05

0.06P

roba

bilit

y

MW

Delayed earliest commissioning year

There are still a number of barriers and issues (Scion, 2008) that would limit the use of wood resource in New Zealand over the shorter term such as:

• forest harvest operational issues and integrating wood residues with the conventional harvest system;

• the need for the development of standards. Wood residues represent a large proportion of the energy and a classification of the different type of wood residues (e.g. water content) will be required; and

• the need to guaranty security of supply by having better information on the actual volume available and the impact of log harvest driven by overseas markets.

Yearly installed capacity

2020 2022 2024 2026 2028 2030 2032 2034 2036 2038 20400

50

100

150

200

250

300

Years

MW

2020 2022 2024 2026 2028 2030 2032 2034 2036 2038 20400

50

100

150

200

250

Years

MW

New assumptionsName Capacity

(MW)FOF (%)

Implied maximum

energy (GWh)

Location Heatrate (GJ/GWh)

Variable O&M, $/MWh

Fixed O&M, $/kW

Capital cost, $/kW

Earliest commissioning year

BioCog1 31 20 217 Kawerau 12000 11.8 100 2850 2020

BioCog2 63 20 441 Central 11400 11.8 100 2800 2024

BioCog3 63 20 441 Whirinaki 10800 11.8 100 2900 2028

BioCog4 31 20 217 Kinleith 10200 11.8 100 2900 2032

BioCog5 21 20 147 Ashley 9600 11.8 100 2800 2036

BioCog6 21 20 147 Nelson 9000 11.8 100 2850 2040

• Total potential installed capacity 150 MW to 230 MW• FOF i.e. capacity factor for baseload – Kinleith 22 %;• 6th power plant in Nelson;• Heatrate was changed from 12000 GJ/GWh (~30%) to values ranging from 30 to 40 %. The heatrate has been decreased by 600 GJ/GWh every 4 years in order to reach 9000 GJ/GWh (~40%) by 2040;• Variable, fixed and capex from the EnergyScape.