Of the countries I’m visiting (UK, Germany, Denmark, Sweden and Holland) they all have a comparable climate (i.e. temperate) and a high level of urbanization, between 83 and 90%, well over the global average of 50% and much more in line with the sort of levels predicted globally by 2080. Germany falls at the top end of this scale with 88% of its citizens leading urban lives. The UK is even higher at 90% which surprises me at first but makes sense when you think of how spaced out we are in the countryside and reinforces the need to develop energy solutions for our urban areas.
Germany has legislated for energy performance in it’s building regulations since the oil shocks of the early 70’s and is home to Passivhaus – the most exacting standard in the world requiring an extremely airtight structure - 3m3/m2/h@50Pa as opposed to 10 under UK building regs and an averaged floor wall and roof u-value of 0.1 compared to the UK Building regulations figures which result in a value of 2.4. Passivhaus is a voluntary standard, not a legal requirement (in Germany that is – it’s a legal requirement in Sweden) but even the German regulations require a averaged u value of 0.3 and a 15% requirement for renewable provision of services load (heating, lighting, hot water) OR the equivalent CO2 reductions from energy efficiency, also limiting efficiencies on boiler plant.
Germany has another voluntary code, the DGNB (Deutsches Gutesiegel Nachhaltiges Bauen) which rates buildings with gold silver and bronze certificates. I expect this is like the AECB (Association of Environmentally Conscious Builders) in the UK. Germany also has a much better record of post occupancy evaluation than us, although that wouldn’t be hard.
(Note to non engineering friends – u value is how much heat gets through the fabric of your building so lower is better and the air tightness figure indicates the number/size of holes you have in your building under pressure. Basically they stick a big fan on the front door and suck the air out to see how much leaks in. The UK value of 10m3/m2/h@50Pa means that at a pressure of 50 Pascals 10m3 of air will be sucked out for every m2 of floor area of the building over the course of an hour)
So the second part of the energy equation – energy efficiency (be lean) is pretty well addressed. What’s the situation with renewables?
Germany has a much higher financial incentive for renewables – they’ve had a feed in tariff since 1991 and since 1999 it’s been worth 2.5 to 4 times the base tariff (in the UK until now the price that energy companies would buy your renewably generated electricity from you was less than you paid to buy it back). During 2006 and 2007 €32.8 billion were poured into energy efficiency measures in existing and new low energy buildings. This makes the UK’s £10.5 million over 4 years (2006-2010) invested in the Low Carbon Building’s Program seem pretty insignificant, even talking into account the difference in size (population Germany 82.4 million, UK 61 million). As a result of all this the levels of renewable energy in Germany were 12% (UK 4.6%) in 2006 and are now around 17%.
So does this results in a lower carbon footprint. Surprisingly - no it doesn’t. Germany has a per capita carbon emission equivalent to 9.49 tonnes of carbon dioxide (UK 8.72) (again 2006 figures form the Zero Carbon Compendium so possible slightly changed since). This is made up of all our activities so perhaps looking at buildings is more appropriate. Their households are responsible for 5.71 tCO2/annum, lower than the UK’s 5.99 although I would have expected the gap to be wider.