Sizing Impacts on Woo

Combustion Performan

November 8, 2012

Nathan Russell, Buildings R&D

New York State Energy Research and Development Aut
Biomass R&D 

Activities and Objectives:• Evaluate energy-efficiency and emissions and compa

fired systems

• Develop advanced commercial and residential techno• Demonstrate advanced technologies in representative 

applications

• Evaluate feedstocks (energy, ash, moisture, trace ele

• Evaluate the net effect of emissions on local air qualit• Evaluate emission control technologies• Provide updated information for the NEI• Provide objective scientific information for the develop

high-efficiency and low-emission biomass heating initNYS

NYSERDA Background
Boilers
Determine the Heat Load

Method Details Manual J, Energy 10, DOE 2 etc

Insulation, solar gain, internal gains, temperature, infiltration, weather data etc

Square footage How big is the house? Previous system What was the output of the previous 

system?

-Over sizing is very common-NYSERDA programs require a Manual J (or equivalent) calculation determine proper HVAC equipment sizing.
Daily heat load profile
Heat Load Analysis
12.5.4 Heat Output Capacity Validation. The first test run m

produce a heat output rate that is within 10% of the manufacturer’s rated heat output capacity (Category IVthroughout the test run and an average heat output rat5% of the manufacturer’s rated heat output capacity. If appliance is not capable of producing a heat output wilimits, the manufacturer’s rated heat output capacity is considered not validated and testing is to be terminatecases, the tests may be restarted using a lower heat ocapacity if requested by the manufacturer.

Nominal Output
Heat Loads

Very Cold Cold Mode

Design Day (DD) Heat Load

65 kBtu/hr 40 kBtu/hr 20 kBt

Boiler output DD 42% 26% 13%70% DD 46 kBtu/hr 28 kBtu/hr 13 kBtBoiler output 70% DD

29% 18% 9%

•White Tag 8 hour average: 116 kBtu/hr •8 hour average, weighted average of outputs at Cat II and III or III and IV• Assume 8 hour average is 75% of max output of 155 kBtu/hr
Weighting Factors
Emissions vs Output
Emissions per Syracuse Da

Conventional HH

RO

Conventional HH

WP

Conventional HH

RO

+

Ref

Three

Stage

HH

RO

European

Pellet

US

Downdraft

RO

02468

10121416

Total PM Emitted per Daily Syracuse Heat Load demand (lbs)

Hydronic Heater Unit and Fuel Type

•Responding to samload with no thermaexcept for US downOWB – 10-14 lbPellet – 0.08 lbMade-in-NY 2-stage ULSHO – 0.00004 l
Emissions

0.000044 0.000068 0.0013 0.0036

0.023 0.023

0.044

0.019 0.029 0.56 1.6

9.9 9.9

19

0.000.050.100.150.200.250.300.35

Natural Gas Ultra Low Sulfur 

#2 

Low Sulfur #2 #2 Home Heating 

Oil

#6* Residual 

Heating Oil

2-Stage 

European^ Pellet

2-Stage 

European^ Sp

Wood

lb/mmBtu

Fuel

Fine Particulate Emissions (Output) for Residential Boilers by Fue

ULS #2 home heating oil, 11 ppm sulfur, 85% efficiencyLS #2 home heating oil, 322 ppm sulfur, 85% efficiency#2 home heating oil, 1520 ppm sulfur, 85% efficiency

* Comm

1x 100x 1,000x

10,000
• Peak performance at steady state and full ou

• Mandates the use of thermal storage• Guidelines vary:

– 6 gallons per 1,000 Btu/hr nominal output– Enough to take full charge of wood– ~ 300 gallons for 100 

Thermal Storage
Pellet Boiler Efficiency vs Ou

0

102030405060708090

0 20000 40000 60000 80000 100000 120000 140000 1600

Output (Btu/hr)

Efficiency (%)
• Sizing a problem for all boilersespecially challenging for solid fue

• More challenging with larger fuel c• Auxiliary thermal storage serves a

major efficiency measure for stagecombustion units resulting in loweemissions

• Pellet boilers also benefit from sm

buffer tanks

Take home
Thank 

You!
PON 2652

• Air quality and health effect studie• Product development• Energy efficient retrofits• Wood chip drying• Pellet trucks• Pellet demonstrations• Grass combustion

$2.5 Million Biomass R&D