2 Energy Building Performance Flashcards
What are the economic and environmental benefits gained from energy conservation in the home?
Switching off lights/ appliances not in use, reduced water use, less drafts, generate renewable energy:
all save money and energy so good for envir. and pockets
What factors are important in the energy efficiency if a building?
Insulation, Air tightness, Glazing
Why is building energy efficiency important in climate change?
Most of the energy produced in the UK (41% as of 2014) is used for space heating/ cooling of buildings
Where does most thermal energy escape from a building, and what can be done to prevent this?
Roof and walls, and insulate these areas
Advantages of an air tight building?
Lower heating bills due to less heat loss
Better performing ventilation system.
Reduced chance of mould and rot because moisture is less likely to enter and become trapped in cavities.
Fewer drafts and thus increased thermal comfort
Single, double or triple glazed windows?
Single not energy efficient
Double more expensive but over long term cheaper and more environmentally friendly
Triple v expensive and more efficient than double but isn’t economically viable
Another name for U-value?
Thermal transmittance (Need to know for exams in case this term is used)
What is a U-value?
U-value is the amount of energy in watts that is transmitted through 1m^2 of a specific material per second when there’s a temp. differential of 1 degree C between the inside and outside.
Units of a U-value? Explain what this means.
W/ m^2/ K. Amount of Watts of energy passing through 1m^2 of a material with a temp difference of 1K
Equation to calculate the rate of heat flow through a section of a wall, and explain the symbols used and their units.
Rate of heat flow = U Value x Area x Temp difference Q = U x A x ∆T Q -> W U -> W/m^2/K or W/m^2/ °C A -> m^2 ∆T-> K or °C
Relationship between Celsius and Kelvin?
1 C = 1K
What is the Zero Carbon Buildings policy?
Zero Carbon Buildings policy requires all new homes from 2016 to mitigate, through various measures, all the carbon emissions on site as a result of the regulated energy use.
The governments zero carbon policy is normally shown as a hierarchical triangle, list beginning at the top what this triangle includes.
Allowable solutions
On-site low carbon heat & power
Fabric energy efficiency
What was the MAXIMUM amount of CO2 allowed to be produced as part of the 2006 Part L building regulations required a for a semi-detached house?
28 kg of CO2 / m^2 / year
Under the Carbon Compliance Target proposed for 2016 what is the new MAXIMUM amount of CO2 allowed to be produced?
11 kg of CO2 / m^2 / year
How is this large decrease in CO2 produced achieved, mainly?
Fabric energy efficiency
On-site low carbon heat and power
How is good fabric efficiency and on-site low carbon heat and power achieved?
Fabric energy efficiency - U values, air tightness, etc
On-site low carbon heat and power - High efficiency boilers, solar PV, solar hot water, on site micro wind turbines etc
What are allowable solutions?
Paying into a carbon fund
Invest in a district heating extension
What is BREEAM?
the world’s foremost environmental assessment method and rating system for buildings developed in 1990
What does BREEAM stand for?
Building Research Establishment Environmental Assessment Method
What will a BREEAM assessment provide you with?
Market recognition for low environmental impact buildings;
Confidence that tried and tested environmental practice is incorporated in the building.
A benchmark that is higher than regulation.
A system to help reduce running costs, improve working and living environments.
A standard that demonstrates progress towards corporate and organisational environmental objectives.
What does BREEAM do?
Addresses wide ranging environmental and sustainability issues and enables developers, designers and building managers to demonstrate the environmental credentials of their building to clients, planners and other initial parties;
by using a straightforward scoring system that is transparent, flexible, easy to understand and supported by evidence-based science and research.
What are the 5 principles of BREEAM?
1 Sustainable solutions. 2 Provides a Framework 3 Sound Science 4 Supports change 5 Delivers Value
What is the state of the Code for Sustainable Homes?
Removed from government policy on March 27th
2015.
