I’d like to propose an adjustment to the columns displayed by default in the “Heatpump + Fabric” view on Heatpumpmonitor.org.
For compliance with the Passivhaus standard, a building must be designed such that its space heating energy requirement averages out at no more than 15 kWh / m² / year. (There is no equivalent target for DHW energy, because that is so highly variable and mostly depends on occupancy levels.) Heatpumpmonitor.org’s “Heatpump + Fabric” view looks like it should provide a great way to check if the Passivhaus properties in the database actually deliver this performance in practice. At first glance it seems that only one of them does - but that’s because the Heat kWh/m² column shown by default is the Combined figure which also includes the energy delivered to the DHW system. To the casual observer, it may seem that the Passivhaus properties are performing much less well than they ought to - which is at odds with the expectation of excellent alignment between their As-Designed and As-Built performance.
With such a high performance fabric, the DHW energy demand in a Passvihaus building can make up a large proportion of the total and tends to dominate the figures - more so than it would in a less efficient building, so displaying the Combined figure for Heat is (even) more of an issue.
Using “Add fields’” to include the Heat kWh/m² and Elec kWh/m² figures from “Stats: Space heating” (and exclude the ones from “Stats: Combined”) presents quite a different picture, with the three Passivhaus properties that have 365 days of data grouped at the top of the list, all neatly meeting the 15kWh requirement. In my opinion, that’s a much better set of columns to show by default. Given that this view has a focus on the building fabric performance (rather than SPF or total cost) it’s legitimate to present a fabric-oriented set of columns by default - provided there’s a hint that the columns relate only to space heating; users can always use “Add fields” to include the DHW energy if they wish.
I therefore propose:
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The “Heatpump + Fabric” view should, by default, include the “Stats: Space Heating” columns for Heat kWh/m² and Elec kWh/m² (instead of the ones for “Stats: Combined”)
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The headings on these columns should be amended to indicate they’re for Space Heating only
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Suggest prefixing with “CH” (and prefix the Hot Water ones with “DHW” or “HW”) so we see e.g. “CH Heat kWh/m²” which isn’t too many extra characters
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The tooltips / helpers need to be tweaked too; currently they say “Electricity consumption per m²” - even for the‘Heat columns
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The initial sort order should change to be on the Heat kWh/m² column, in Ascending order
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We add the “% DHW” column from the "Stats: Hot Water” group to the default column list, since that is helpful in understanding the split of energy usage
- I note that the 66% DHW usage for the Chiswick Passivhaus is the highest percentage on the whole database
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We retain the combined SPF column as it is
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This one is more debatable but I think overall SPF is more useful than e.g. the space heating-only SPF
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I think it’s interesting that these high-performance buildings have rather modest SPF figures, despite them delivering incredibly low space heating costs, confirming that a high SPF isn’t the primary goal
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I’m willing to have a stab at amending the code (looks like it’s only system_list.php that’s affected) and raising a Pull Request but I wanted to socialise the principle of changing the default columns here first. (I’m equally happy for someone more familiar with the code base to make the changes instead 
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