Chapter 17 Flashcards
FEH
final energy use for heat
in OECD countries, nat. gas is the primary source of energy for heat followed by oil and coal, which make up about 85% of final energy use for heat (FEH).
in developing world, a substantially higher reliance on biomass for residential heating and cooking applications reduces but does not eliminate the contribution of fossil fuels in FEH
kiln
production of cement happens in a kiln
an insulated oven used to raise the temperature of the mix to 1500 degrees C.
blast furnace
iron and steel.
the process of converting iron ore into higher-quality pig iron primarily involves using blast furnaces
blast furnaces use heated air at over 1000 degrees C to strip off impurities and remove oxygen from the irn ore. reducing the carbon content further through a blast furnace or electric arc furnace makes steel
deforestation
meaningful source of CO2 and methane
process heating
industrial process heating = a category of material transformation processes that use thermal energy to refine materials, after their properties, or remove unwanted moisture or other contaminants. 3 primary routes:
(1) fuel-based process heating
(2) electric-based process heating
(3) steam-based process heating
Best Available Technology (BAT)
a define standard established by governments to describe the state of the art performance of a particular technology or process available in the marketplace. defined by enviro impacts, discharges of waste, energy efficiency
fuel switching
coal to gas switching may reduce some of the undesirable effects of pollution and emissions from cogeneration.
fossil fuels to renewable switching can help improve emissions characteristics and dampen fuel price volatility and dependence
ESCOs
energy service companies – can help mitigate risks and uncertainties for users through guaranteed energy savings or cost-sharing basis
commercial or non-profit business providing a broad range of energy solutions including designs and implementation of energy savings projects, retrofitting, energy conservation, energy infrastructure outsourcing, power generation and energy supply, and risk management.
sub-metering
to pay for energy consumption, the occupant either receives a direct bill for their individual use (sub-metering) or a pro-rate share of the total building’s bill based on some estimation method (P-A problems when choice of energy consumption separated b/w building owner and tenant)
triple net lease
tenant is responsible for the energy bill despite having very little say over the construction or equipment choices that went into that building (common in US)
co-generation
these facilities capture the waste heat from electricity generation to support the thermal needs of the building, can enhance the economics for this DG
MUSH market
INSTITUTIONAL (building category)
Municipal & state govts
Universties/colleges
Schools (k-12)
Hospitals
third segment of buildings = institutional. large multi-user facilities. these are increasingly designed to be able to island (separate from the grid)
HVAC
Building thermal applications.
70% of energy consumption for buildings in cold climates goes to space heating and appliances.
heating, ventilation, air-conditioning
heat pumps
generating heat, and by running in reverse generating air-condition, is usu. done by a heat pump.
heat pumps comprise a vast range of technologies that can move heat (through the use of a liquid or gaseous refrigerant carrier from one location to another: source –> sink).
ground-source heat pump
geothermal heat pumps.
require equipment to circulate water (or another refrigerant) in a closed or open loop under the ground, taking advantage of the natural temperature differentials b/w the ground and the ambient air. efficient, but v. expensive.
coefficient of performance (COP)
measures relative efficiency of heat pumps
How efficiently can a device convert input heat into the desired thermal output determines its fuel needs, cost, and overall desirability as a solution.
the ratio of the heat supplied to or removed from the reservoir as a percentage the work consumed by the pump
building envelope
a set of features (common to all buildings) which determine the relationship between the building and the external conditions
roofs ventilation and air leakage walls windows and doors floors and basements
U factor
one metric of thermal efficiency of building components
the rate at which the window, door, or skylight conducts non-solar heat flow. lower u-factors represent materials that have increased insulation protection, and these values can be lowered through the use of glazing, better materials, more layers/panes, adding space b/w the layers filled with air, gas, or even creating a vacuum
R value
insulation elements in walls, roofs, basements are often measured w/ R-value
the reciprocal of U-factor used for conductive forcing above. R-values = materials with better insulation properties.
heavy fuel oil
aka residual oil, makes up the grades of No. 5 and No. 6 fuel oils. high viscosity, need to be pre-heated or blended with other, lighter fuels to make them combustible or pumpable.
combined heat and power (CHP)
the process whereby the waste heat from electricity generation can also be captured and put to work for productive purpose.
sometimes this productive use is to increase the efficiency of electricity generation itself, but more often the low quality heat of targeted toward local thermal needs like space or water heating
district energy
district heating & cooling systems = district energy.
not sources of energy themselves, but methods of capturing heat from a source and moving it to a sink using large integrated networks of delivery systems across multiple buildings/users.
building management systems (BMS)
smart controls for integrating thermal systems. modern intelligent control systems that integrate both electric and thermal aspects to their overall control schemes
repowering
retrofitting infrastructure or asset. when this is done using electricity generators, thermal plants or even engines – it’s called repowering an asset.
Repowering is the process of replacing older power stations with newer ones that either have a greater nameplate capacity or more efficiency which results in a net increase of power generated.[1] Repowering can happen in several different ways. It can be as small as switching out and replacing a boiler, to as large as replacing the entire system to create a more powerful system entirely.
