Passive house requirements for new build

[dnb]

I have been looking at the requirements for building a passive house to see how viable it is for a new build I am considering. It seems new materials in the past few years have made it easier to achieve the requirements but one of them is puzzling me as to what it means:

The primary energy usage requirement of less than 120 kWh/m^2/year (first off, being pedantic, why isn't this expressed as kW/m^2?). My understanding is that this primary energy must cover heating, hot water, lighting, cooking, fridge, freezer dish washer etc. It equates to over 20,000kWh per year for the approximately 180m^2 house I would like to build. This is rather a lot more energy than my current inefficient old house of similar size uses annually, and a passive house will be much easier to heat. This is where a large chunk of the old house energy budget is spent. I must be misunderstanding something here - can anyone explain what I am not accounting for?

I've tried looking at the PHPP demo but suspect I really need the instructions to get a clear answer.

Thanks.

[dnb]

robemcdonald said:

You may be better off looking at just following the principle.

This I have heard from other people too. I may well just follow the principle because it does look to be a coherent and sensible set of aims (apart from the primary power usage one I am clearly not understanding!) and be happy to end up with a house that exceeds the current self build requirements.

It does seem like a good idea to achieve the passive house standard for insulation etc since every modern house I have seen has needed mechanical ventilation for air quality, so why not try to make it do the heating and cooling as well to reduce complexity?

I would like to understand the primary power requirement though!

Outline spec from here:
http://www.passivhaus.org.uk/standard.jsp?id=18

Edited by dnb on Monday 22 August 22:41