Wood to Warmth – Case StudiesAlison Wilshaw, TV Energy

10 April 20231

Flint Cottage

Project description• Zero carbon house• 3/4 bedroom house,

Brightwalton, Berkshire• 7.7 kW Charnwood stove

+ back boiler with 400 litre thermal store.

• Solar thermal & electric boost.

• Off gas, rural location, • Meets Code Level 3

10 April 20232

Fuel Supply• Logs from local tree

surgeons & estate woodlands

• ½ tonne trailer loads, £120/tonne

• 10 loads per year, £600

10 April 20233

Flint Cottage

Flint Cottage

Project economics• Installed costs:

£2,500 (stove, liner)+ £3,400 (store)

• Predicted annual energy generation: 12,000 kWh (wood)

• Wood fuel use: 5 tonnes/year

10 April 20234

Flint Cottage

Payback• Capital premium vs.

oil: £1,100• Annual savings vs.

oil: £250• Simple payback in

years: 4.4

10 April 20235

Curridge Primary School

Project description• 50 kW Herz Firematic

chip boiler + buffer store

• Small village primary school near Newbury, West Berkshire

• TV Bioenergy operates boiler under an ESCo contract

10 April 20236

ESCo heat contract•ESCo owns boiler hardware, controls the fuel quality, & guarantees heat•Local estate supplies wood chip via truck•Local operative for routine operation & maintenance on site

10 April 20237

Curridge Primary School

Curridge Primary School

• Installed system cost: £65,000 (total)

• Annual energy generation: 40,000 kWh/year

• Wood fuel use: 20 tonnes/year

• Expected lifetime: 20 years

10 April 20238

Englefield Estate

Woodchip boiler and districtheating network

• 500kW woodchip boiler• Estate-supplied wood fuel• 800m of district heating

network, existing local boilers to remain

• Located near Theale, Reading

10 April 20239

• Mainly residential loads, plus church, offices, glasshouse, swimming pool

Englefield Estate

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Lessons Learned from Austrian Visit

Select central boiler location carefully• Consider suitability of existing buildings (space,

layout)• Option of purpose-built plant room

Allow space for additional central plant to be installed when local boilers require replacement

District heat mains should also be sized for additional future heat supply

10 April 202311

Englefield Estate

Fuel Supply

• Wood fuel to be sourced from the estate (~1500 Ha)

• Either sent to local aggregator for chipping, or chipped on site through hired chipper services

• Could be chipped direct into fuel store to minimise handling

10 April 202312

Englefield Estate

Englefield Estate

• Installed system cost: ~£400,000• Annual energy generation: 800,000 kWh/yr• Wood fuel consumption: 280 tonnes/year

@30%MC• Expected lifetime: boiler 20 years, district

heating network 50 years• Annual savings: £20,000/yr• Annual income from RHI: ~£40,000 –

50,000/yr• Simple payback: 20 years (without RHI),

6 years (including RHI)

10 April 202313

Hillfields Farm

Project description• 220 kW• Boiler, buffer tank &

district heating• Supplies 90% of heat

(10% from solar / electric)• Heating & HW for house,

offices, swimming pool • Alternative to oil• Nr Pangbourne, Berkshire

10 April 202314

• Typical estate model• Fuel from own woodland on

site• No oil backup system• Dedicated fuel store with

transfer auger• Uses own chipper and trailer• Contracted to sell surplus via

TV Bioenergy to local boilers

10 April 202315

Hillfields Farm

Hillfields Farm

Project economics• Installed system cost: Boiler £60k +VAT,

solar £20k +VAT• Annual energy generation: 350 MWh (+32

MWh solar)• Predicted annual savings: c. £13k + £1.2• Wood fuel consumption: 160 tonnes/year• Expected lifetime: min. 15 years

10 April 202316

September 201017

Hillfields Farm

Solar for houseSolar for

pool

Biomass boiler