Technical Definition from UKGBC:
Net-Zero Energy Building has multiple definitions this one is from UKGBC.
1.1 Net- Zero Carbon - Construction
1.2 Net- Zero Carbon - Operational Energy
1.3 Net- Zero Carbon – Whole Life (yet to be defined)
Net- Zero Carbon - Construction
When the amount of carbon emission associated with a building product and construction stages up to practical completion is zero or negative, through the use of offsets or the net export of on- site renewable energy.
Net- Zero Carbon – Operational Energy
When the amount of carbon emissions associated with the building’s operational energy on an annual basis is zero or negative. A net zero carbon building is highly energy efficient and powered from on-site and/ or off-site renewable energy sources, with any remaining carbon balance offset.
Action taken from UK Parliament:
In May 2019, the Committee on Climate Change (CCC)—as requested by the Government—set out a blueprint for how the UK could viably build a net zero greenhouse gas emission economy by 2050, to pursue the 1.5 degrees aspiration of the Paris Agreement.1 In June, Parliament enshrined into law the net zero target, which commits the UK to reduce emissions by “at least” 100 per cent below 1990 levels in 2050.2 This will require deep emissions reductions across the economy, with any residual sources offset by removals of CO₂ from the atmosphere
So from this we understand it is an issue that we all need to participate towards net-zero energy building.
Energy Efficiency and Net Zero Energy Building:
Energy Efficiency can be calculated by Type of property, Age, Building system and methods, size, heating system, insulation, double glazed, type of lighting system used. All these categories I’ve taken into account to produce energy efficient certificate in UK for domestic buildings we all our familiarised with the certificate. Average UK homes how the energy efficient bands between E and C. To improve the Energy efficiency in the residential properties the key elements are
Double or triple glazing- this will not only improve the indoor temperature also reduced noise penetrations.
Loft insulation- as we all know hot air rises so a lot of installation(Will prevent heat escaping this will result in your electricity bills. The loft insulation thickness should be minimum 270 MM.
Wall Insulations- cavity wall, is the 2 wall with cavity (gap) in between can be filled with polystyrene, mineral wool or foam. The wall insulation will help heat to retain within building.
Efficient heating methods- this depends upon the technology present today to improve and minimise efficiency off heating usage
The above methodologies helps us have an energy-efficient building. Net Zero energy building is the building which can produce its own energy within its site.
For example: introducing Solar panels on the rooftop with 23degree -50 degree inclined (can produce maximum energy if the solar panel faces south, as it gets most of the sun radiation through-out the year) or local renewable energy sources.
Renewable energy sources for net- zero energy Buildings:
Naturally available energy sources or freely available energy resources like sun, wind, water and heat can be converted into Electricity.
Solar Panels: this is a very well-known methods of producing electricity within property site. It is important to understand the Efficiency and the efficacy of using Energy produced from solar panels if the energy is not sent back to the grid, then need to have all battery to store the energy produced from the sun through solar panels.
Average Energy/ household/ year
|
4,200 KWh/annum
|
Average energy bill for a 3 bed room house/ year
|
1,588£/annum
|
Average Energy/ Photo Voltaic/ Year
|
3,400 KWh/annum
|
Energy provided by solar panel is
|
80% /annum
|
Cost for PV installation for 28m2 or for 16 Panels with batteries
|
7,000£
|
Energy Bill after installing Solar panel is
|
302£/ Annum
|
Savings on Energy Bill is
|
1286£/ Annum
|
Initial Investment on solar panel recovered in
|
5 years
|
Environmental impact of using Solar panels by a standard house n UK reduces CO2 emissions of
|
1.2 tonnes/ Annum
|
Note: these values of photo voltaic is applicable for an ideal situations. All the values at according to year 2020.Insentives are available for installing PV’s with conditions applied.
Wind Turbines: This can be one of the alternative or combined renewable energy resources for a property depending on the location of the property. To install a wind turbine minimum wind speed should be 7m/s, this condition is present in most of the UK. It can be installed over the roof or separately on a shaft. The electricity generated depends on height of the shaft mounted, length of the turbines and constant wind flow.
Average Energy/ household/ year
|
4,200 KWh
|
Average energy bill for a 3 bed room house/year
|
1,588£/ Annum
|
Average Energy/1.5KW roof-top wind turbine/year
|
4,000 KWh/ Annum
|
Energy provided by Wind turbine/year
|
95%
|
Initial roof-top 1.5KW wind turbine installation cost
|
4,255.62£
|
Energy Bill after installing roof top wind turbines is
|
75£/ Annum
|
Savings on Energy Bill is
|
1,512.3£/Annum
|
Initial Investment on solar panel recovered in
|
2.8 years
|
Environmental impact of using roof-top wind turbines in UK reduces CO2 emissions of
|
4.5 tonnes/Annum
|
Note: the energy calculated is for roof top turbines as standalone turbine in urban areas can be objected from planning permissions.
There are more renewable energy sources to produce electricity but applicable for rural set-up and large scale electricity generation. It can also be use in small scale but not as beneficial as solar and wind turbines.
Biomass:
This is the process of producing electricity by burning biological matters by boiling water to help rotate the turbines to hence produce electricity. If this energy not used carefully and thoughtfully we end up giving out more CO2 to atmosphere. Example: if the site has no sufficient biomass produced or any local source available the regular transportation to collect biomass fuel will cause more CO2 emission than reduce.
Hydro:
Energy produced using running water, the quantity of energy depends on the intensity of water flow. The water flow helps to rotate turbines, turbines connected to electricity generators to produce electricity similar to biomass. This process is applicable only to site close to flowing water source.
Conclusion:
A building with energy efficient construction techniques and materials consumes less energy. Energy required by the energy efficient building is generated on-site is called NET-Zero Energy Building.
Sources:
Sources:
Net Zero Carbon Buildings UKGBC Document
Energy and carbon audit of a rooftop wind turbine. Research gate.net
Domestic Wind turbines. Go compare.co.uk
No comments:
Post a Comment