Energy demand analysis for small and medium scale heat users in Rotorua aiming at converting existing heating systems to bioenergy

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Energy demand analysis for small and medium scale
heat users in Rotorua aiming at converting
existing heating systems to bioenergy

• Dr Per S. Nielsen,
• Mr. G. Estcourt,
• Mr. M. Shepherd

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Acknowledgement

• EECA
• Rotorua Energy Charitable Trust

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Introduction

• Evaluation of heat demand at school in Rotorua
• The driver for us has been to evaluate the long
  term competitiveness of wood pellet heating
  systems.

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Energy Grade Optimisation
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Energy demand at schools

• Electricity
• Space heating
• Water haeting

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Space heating profiles

• Annual profile
• weekly
• Daily

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Energy use survey on Schools in Rotorua

• 27 schools
• Primary as well as secondary schools
• Interview with each school
• Basic energy sue information

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Results

• 40-45 of energy use is relate4d to space haeting
• 45 of the schools use coal as the main fuel
  source for sapce heating in old buildings
• In prefabs electricity is used for heating

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Fuels sources at the schools
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Heating costs related to type of fuel use
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Heating costs per student
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regression
kWh/year
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Energy PRO evaluation
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Conclusions

• 45 of the schools have a coal boiler, which
  heats the part of the school (more than 20 years
  old).
• In new buildings electricity heaters are the
  preferred solution.
• On fuel costs alone, a wood pellet cost of 6c/kWh
  will be competitive with the school on
  electricity and electricity/coal and comparable
  to natural gas, but not competitive to the
  schools using coal.

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Acknowledgement

• EECA
• Rotorua Energy Charitable Trust