I'm using VE-SBEM for a project where I have included a solar water htg system but it doesn't appear to have any impact on the the results. Is this a bug?
I'm also struggling to find information in the guides or FAQs on the parameters for solar water htg, can you point me to the correct user guide?
VE-SBEM - solar water heating
Re: VE-SBEM - solar water heating
I've now tried this with multiple projects and added different solar water heating set ups and each time I get no change in the results. This is definitely not working for me. Does it work for anyone else?
Been looking through the 'user guides' but there is nothing on this, just a paragraph saying this is where you set up solar water htg for sbem...
Been looking through the 'user guides' but there is nothing on this, just a paragraph saying this is where you set up solar water htg for sbem...
Re: VE-SBEM - solar water heating
Hi, did you get this resolved? I am facing the same problem. I assume i have missed something somewhere?
Re: VE-SBEM - solar water heating
No, not resolved. Would be good if someone from IES acknowledged it.
I'm sure this must have come up before as I can't be the only person using a solar water heating system.
I'm sure this must have come up before as I can't be the only person using a solar water heating system.
Re: VE-SBEM - solar water heating
This is a common question and it is usually a result of users keeping the defaults for the SES (it is not a bug!). These defaults are not realistic and it is expected users would enter their own inputs for their SES.
You need to make sure the tank volume isn’t too large for the panel area you’ve entered (BRE recommends assuming 5 litres storage per m2 of solar collector area). Also, edit default heat transfer rate if it is still 5.4 W/K; a more sensible figure would probably be 130 W/K.
It is important to remember that SBEM is only a compliance tool so you shouldn’t be using it for design purposes. The BRE (who develop the SBEM engine) regularly state this in the emails from their helpline. I’ve copied an example of one of their responses below.
Please note that SBEM is not a design tool, and the most appropriate modelling tool for design purposes should be used. Once the valid design configuration has been set up using the appropriate modelling tool, the relevant parameters can then be input into SBEM to assess compliance. For e.g., the user should not be using SBEM to “experiment" with the performance parameters in order to make a building pass compliance. Even if a building passes compliance in SBEM, this does not prove that the design will work in practice.
Please refer to the SBEM Technical Manual (available for download from the NCM website at http://www.ncm.bre.co.uk) for details of the methodology, equations, and references used for the solar water heating calculation (as well as other calculations) within SBEM v4.1.
http://www.ncm.bre.co.uk/filelibrary/SB ... 1Mar11.pdf
You need to make sure the tank volume isn’t too large for the panel area you’ve entered (BRE recommends assuming 5 litres storage per m2 of solar collector area). Also, edit default heat transfer rate if it is still 5.4 W/K; a more sensible figure would probably be 130 W/K.
It is important to remember that SBEM is only a compliance tool so you shouldn’t be using it for design purposes. The BRE (who develop the SBEM engine) regularly state this in the emails from their helpline. I’ve copied an example of one of their responses below.
Please note that SBEM is not a design tool, and the most appropriate modelling tool for design purposes should be used. Once the valid design configuration has been set up using the appropriate modelling tool, the relevant parameters can then be input into SBEM to assess compliance. For e.g., the user should not be using SBEM to “experiment" with the performance parameters in order to make a building pass compliance. Even if a building passes compliance in SBEM, this does not prove that the design will work in practice.
Please refer to the SBEM Technical Manual (available for download from the NCM website at http://www.ncm.bre.co.uk) for details of the methodology, equations, and references used for the solar water heating calculation (as well as other calculations) within SBEM v4.1.
http://www.ncm.bre.co.uk/filelibrary/SB ... 1Mar11.pdf