4. Water heating requirement

sap2012.SAP_worksheet.water_heating_requirement.water_heating_requirement(assumed_occupancy, V_dm_table_1c, days_in_month, T_table_1d, water_storage_loss_manufacturer, temperature_factor_table_2b, storage_volume_litres, hot_water_storage_loss_table_2, volume_factor_table_2a, Vs_appendix_G3, solar_storage_WWHRS_factor, primary_circuit_loss_table_3, combi_loss_table_3, solar_DHW_input_appendix_G)[source]

Calculates water heating requirement, Section 4.

Parameters:

  • assumed_occupancy (float) – See (42). Calculated using equation from (42). If TFA > 13.9, N = 1 + 1.76 * [1 - exp(-0.000349 * (TFA -13.9)2)] + 0.0013 * (TFA -13.9). if TFA =< 13.9, N = 1. Where TFA is the Total Floor Area.

  • V_dm_table_1c (list (float)) – See Table 1c.

  • days_in_month (list (int)) – List of the number of days in each month of the calendar year.

  • T_table_1d (list (float)) – See Table 1d.

  • storage_volume_litres (int) – See (47). Value is 0 if no tank in dwelling. If no tank or combi boiler enter ‘0’. If community heating enter ‘110’.

  • water_storage_loss_manufacturer (float or None) – See (48). Value is None if unknown or no tank in dwelling.

  • temperature_factor_table_2b (float) – See (49/53). Value is 0 if no tank in dwelling.

  • hot_water_storage_loss_table_2 (float) – See (51). Value is 0 if no tank in dwelling.

  • volume_factor_table_2a (float) – See (52). Value is 0 if no tank in dwelling.

  • Vs_appendix_G3 (float or None) – See appendix G3. Only applies where solar storage is within dwelling.

  • solar_storage_WWHRS_factor (int or None) – Applies to dwellings with solar storage.

  • primary_circuit_loss_table_3 (float) – See (59). Values found in Table 3.

  • combi_loss_table_3 (float) – See (61). Values found in Table 3.

  • solar_DHW_input_appendix_G (float or None) – See Appendix G.

Returns:

A dictionary with keys of ( annual_hot_water_usage_litres_per_day, hot_water_usage_in_litres_per_day_monthly, energy_content_of_water_used, distribution_loss, energy_lost_from_water_storage, water_storage_loss_monthly, total_heat_required_for_water_heating, output_from_water_heater_monthly, heat_gains_from_water_heating_monthly )

  • annual_hot_water_usage_litres_per_day (float): (43) in L.

  • hot_water_usage_in_litres_per_day_monthly (list (float)): (44) in L.

  • energy_content_of_water_used (list (float)): (45) in kWh/month.

  • distribution_loss (list (float)): (46) in kWh/month.

  • energy_lost_from_water_storage (list (float)): (50/55) in kWh/month.

  • water_storage_loss_monthly (list (float)): (56) in kWh/month.

  • total_heat_required_for_water_heating (list (float)): (62) in kWh/month.

  • output_from_water_heater_monthly (list (float)): (64) in kWh/month.

  • heat_gains_from_water_heating_monthly (list (float)): (65) in kWh/month.

Return type:

dict