¶ Other energy saving devices
The DEAP Methodology and software have evolved to cater for new and innovative technologies. If you are assessing a dwelling including an innovative technology not necessarily represented in DEAP, contact the BER Helpdesk by e-mail at [email protected] to ascertain the correct approach. In some cases, the technology may be catered for within the current DEAP methodology based on guidance from the BER Helpdesk. Otherwise:
- The technology may be considered for future inclusion in the DEAP methodology;
- The technology may be deemed inappropriate for inclusion in the DEAP methodology and should not be accounted for in BER assessments.
The “Renewable and Energy Saving Technologies” section in DEAP is discussed in DEAP Appendix Q, including a listing of technologies catered for therein.
Guidance on re-use of data for other renewables can be found here
¶ Flue gas heat recovery systems (FGHRS)
A Flue Gas Heat Recovery System (FGHRS) is a mechanism to recover heat from a boiler’s exhaust gas, improving the efficiency of the boiler. The recovered heat can be used to pre-heat water entering the boiler. BRE provide a spreadsheet for deriving the energy saved by these devices when registered on BRE’s products database.
When using the above spreadsheet, first select the installed FGHRS from the “Select FGHRS” tab -> “Index Number chosen). Then, under “Calculate savings” / “Worksheet data” select entries as follows:
Table 8.5 - Data entry for FGHRS
| Data Required | Value |
|---|---|
| Fuel | LPG/Gas/Oil |
| Boiler | Regular/Combi |
| Condensing or Non-Condensing | Condensing or Non-Condensing |
| Total Dwelling Floor Area | From DEAP Building |
| Volume of Hot Water store | From DEAP Water Heating |
| Temperature Factor | From DEAP Water Heating “Temperature Factor Unadjusted” x ”Temperature Factor Multiplier” |
| Water Storage heat loss for 1 month | From DEAP Water Heating “Storage Loss” (divided by 12 to give 1 month) |
| Primary Circuit Heat los | From DEAP Water Heating “Primary Circuit Loss” |
| Combi Loss for 1 month | From DEAP Water Heating “Additional Loss for Combi Boiler” (divided by 12 to give approximately 1 month) |
| Contribution from Solar Water Heating | From DEAP Water Heating tab “Solar Hot Water Input” |
| Efficiency of space and water heating | From DEAP Space Heating > Heat Sources and DEAP Water Heating > Heat Sources (water heating efficiency repeated for each of the 12 months) |
| Energy Saved by WWHRS | Set to ‘0’ in this instance. |
| Main heater fuel usage |
|
| Fraction of heat from Secondary/Supplementary system | From DEAP Space Heating > Heat Sources tab |
| Electricity used by Keep-hot facility | From DEAP Water Heating |
The spreadsheet uses this information to calculate the annual energy saved by the FGHRS in kWh. This number is input into the DEAP software in the Renewables section. The example below shows how the data for an FGHRS unit which saves 350kWh per annum is entered into DEAP:
