BIOMASS AS A RENEWABLE RESOURCE:

Application in Buildings case study

The most common biomass used is “woody” biomass comprising of trees and woody plants and leaves, grown in a forest, woodland, or rangeland environment that are the by-products of forest management.

The biomass is typically burned as chips on a large-scale and wood pellets for small-scale applications.

KETCHIKAN FEDERAL BUILDING

Location: Ketchikan, AlaskaPurpose: Hot water distribution system

Application chosen: biomass heating technology by means of wooden pellet boiler system

Boiler specifications: 1 million BTUs per hourEfficiency: 85.6%

METHODOLOGYThe wood pellets are stored in a silo outside of the building and are augured into the building when the low-level signal is given from the fuel bin level sensor. The pellets automatically replenish the fuel bin and the conveyor stops when the upper level sensor is triggered.

The fuel is burned efficiently using staged combustion air injection. The hot flue gas travels through a bank of tubes where the heat is transferred to the water that surrounds the tube bundle. This is known as a “fire tube” design.

This boiler design is equipped with an automated mechanical cleaning system that periodically removes ash build-up from the tubes. This is done online to avoid interruptions in the heating process.

ENERGY ANALYSIS

CONCLUSION environmental friendly system of heat generation.

No wastage of fuels like diesel

additional energy savings in a building.

Lower emissions of co2

Initial cost of execution is high.

Can be installed only in places abundant with biomass sources

GEOTHERMAL ENERGY RESOURCE

GALT HOUSE EAST HOTEL AND WATERFRONT OFFICE

BUILDINGSLocation: Louisville, Kentucky

Tag: largest Geothermal Heating and cooling system in the US

Project description: 4,500 tons Geothermal Heat Power system

67 MM btu/hour heating

Heating and air conditioning is provided for 750 square foot hotel rooms, 1800 square foot apartments, square feet of meeting rooms, ballroom and public space, and square feet of office building totalling 1,740,000 square feet.

The system can extract 2800 gallons per minute of ground water from four wells at and can either remove energy from the well water for heating or add heat to the well water from the air conditioning. The water is then discharged into a storm water system.

Construction and operation costs are extremely low compared to other systems commonly installed in a similar complex.

SYSTEM DESIGNFor the Galt House East Hotel, ground water at 58'F is pumped into a 140,000 gallon reservoir under the mechanical room.

Water from the reservoir is circulated through plate/ frame heat exchangers. This separates the ground water from closed loop circulation systems in the buildings.

The closed loops are connected to water source heat pumps which can absorb heat from the loop water or reject heat into the loop water, depending on the requirement of that space. Any space can have heating or cooling at any time.

During spring and fall, the use of thermal storage allows the controls to shut down the well pumps (sometimes for as long as a week). The Btu's stored in the reservoir during the day from air-conditioning can be used to heat the building at night

The pumps normally operate at 25% to30% of full load current due to water regulating valves and variable frequency drives on the circulating pumps. With 375hp pumps (three- 100hp pumps and one-75hp pump) running at70% less than full load, savings are $111,502 per year.

Chemical emissions from cooling tower bleed and boiler blow down also are eliminated by the geothermal heat pump system

Due to the reduction in power required, principle emissions from the power station were reduced by 7,870,0001b per year of COr; 44,000 Ib per year of SOr; 33,000 lb per year of NO,; and 5,500 lb per year particulate.

EVALUATION STATISTICS

Comparative test results between Galt east hotel with the geothermal heating and cooling and Galt hotel with conventional heating and cooling systems