Jump to content

Recommended Posts

Hey everyone.

 

We are building on Bantaskin Street in Maryhill, Glasgow. Foundations complete and we are now working on the frame onsite.

 

One of our build requirements (via Glasgow City Council who have initiated this project) is that we meet the "Silver Active" energy efficiency rating. Our architect has specced a whole bunch of things for us and we have the certificate. I spoke to him and asked about changing things/moving things around, and how to check whether or not we would still meet Silver Active and he wasn't very helpful.

 

Does anyone know more about this? I'm thinking we should remove 5 PV panels, which might not do a huge amount in grey Glasgow, (but cost a fortune!) and try to come up with something more clever? We are hands on, and working with a small budget, so want to be creative and innovative here if possible.

 

Ideas and thoughts welcome!

 

Thanks

 

Joanna

Screen Shot 2019-07-02 at 09.10.51.png

Link to comment
Share on other sites

Found some info here..

 

https://www2.gov.scot/resource/buildingstandards/2017Domestic/chunks/ch08s02.html

 



• Silver Active level – This is the same as the silver level but, in addition, the dwelling includes the use of a low and zero carbon generating technology (LZCGT) in respect of meeting at least one of the aspects: Silver 1, Silver 2 or Silver 3. 

 



Aspect Silver level 1: Carbon dioxide emissions

All new dwellings that meet or exceed the Target Emissions Rate (TER) detailed in Section 6, Energy of this Handbook, will automatically meet the Silver level criteria in respect of CO2 emissions. This is due to the 21% improvement on the 2010 standards that occurred in October 2015.

Aspect Silver level 2: Energy for space heating

Maximum annual demand for useful energy for space heating should be:
  • 40kWh/m2 for houses, or

  • 30kWh/m2 for flats or maisonettes

To assess, the output from box no.99 of the SAP 2012 DER worksheet should be no more than the figures above.

Aspect Silver level 3: Energy for water heating

At least 5% of the dwelling or domestic building’s annual energy demand for water heating should be from:

  • heat recovery and/or renewable sources with little or no associated fuel costs (e.g. solar thermal water heating and associated storage or heat recovery from greywater) that are allocated for water heating.

To assess, the annual energy demand for water heating in kWh multiplied by 0.05, should be no more than the contribution from specified equipment that uses renewable energy and/or heat recovery. A SAP spreadsheet is available for this calculation here: http://www.bre.co.uk/sap2012/page.jsp?id=3817.

 

So you need to know how much solar PV is required to meet 1,2 or 3 above.

Link to comment
Share on other sites

42 minutes ago, Temp said:

40kWh/m2 for houses, or

Is that regardless of the source?

I use about 15 kWh/day for space heating, but only for about 100 days a year (though I am in a warm place).

So that works out at 30 kWh/m2.

So this seems quite achievable even with resistive electrical heating.

Edited by SteamyTea
Link to comment
Share on other sites

2 minutes ago, SteamyTea said:

Is that regardless of the source?

I use about 15 kWh/day for space heating, but only for about 100 days a year.

So that works out at 30 kWh/m2.

So this seems quite achievable even with resistive electrical heating.

 

It says "Maximum annual demand for useful energy for space heating "

I think "useful" means heat output, this it is equivalent of saying not more than 40kWh/m2 heat loss per year. So doesn't matter where it's coming from (and conversely, getting it from a 300% efficient heat pump vs a resistive heater won't make and difference to meeting this specific goal)

 

 

As @Temp mentioned the solar PV is for  the "Silver Active" add on:

""

7.1.5 Silver Active level

This is the same as the silver level but, in addition, the dwelling includes the use of a low and zero carbon generating technology (LZCGT) in respect of meeting at least one of the aspects: Silver 1, Silver 2 or Silver 3. This level is primarily to assist local authorities to meet their obligations under Section 72 of the Climate Change (Scotland) Act 2009 by identifying the use of LZCGT. In this respect, LZCGTs include: wind turbines, water turbines, heat pumps (all varieties), solar thermal panels, photovoltaic panels, combined heat and power units (fired by low emission sources), fuel cells, biomass boilers/stoves and biogas.

"""

(my emphasis)

 

 

so if you remove PV you need to add one of those other things instead, and use it to meet that level 2.  A heat pump is probably simplest  option, as you need some sort of boiler/heater anyway (and could save you on gas or oil supply), and it should be feasible to meet the 40kWh/m2/yr easily enough if correctly sized.

 

 

 

 

 

Link to comment
Share on other sites

Even without PV my energy use is less than the requirement above.

 

It looks like you must have solar THERMAL to heat at least 5% of your DHW but as long as you have enough insulation you could get away with no solar PV if I am reading it correctly but you will probably have to heat the house with a heat pump (a good idea anyway)

Link to comment
Share on other sites

21 hours ago, Joanna Susskind said:

 

I'm thinking we should remove 5 PV panels, which might not do a huge amount in grey Glasgow, (but cost a fortune!)

5 modules is probably around 1.5 kWp.  This is not a very large system, so should not cost much, but as some have found, on a new build, it can cost less that tiling a roof.

PV works when it is cloudy, solar thermal is the one that does not perform well in lower light levels.  You can use PV to heat water.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...