## 2 Policy Goals of Urban Transition in the Oresund Region
### Macroeconomic Potential of Energy Refurbishing the Building Stock by Building Segment  
Statistics on energy consumption in buildings and in private households serve as baseline data for calculating the energy saving potential and economics of renovations of the existing building stock, Table 4. Documentation of the economics at project level are available on construction and refurbishing according to new energy standards under different assumptions of technical solutions and  
\begin{table}
\begin{tabular}{c c c} \hline
**Percentage of CO\({}_{2}\) Emissions From** & **2009** & **2012** \\ \hline Electricity & 49 & 44 \\ District heating & 25 & 25 \\ Traffic & 20 & 27 \\ Individual heating \& gas & 2 & 2 \\ Other & 4 & 2 \\ Total & 100 & 100 \\ Estimated total CO\({}_{2}\) emissions & 2,654,129 tons & 1,958,886 tons \\ \hline \end{tabular}
\end{table}
Table 3: Contribution of CO\({}_{2}\) by consumption type, Source: Copenhagen climate statistics, Copenhagen municipality and COWI (2010, 2013) [22,23].  
performance, energy prices, and interest rates [20,24,25]. In Sweden the building stock represents about 30% of total energy consumption [16]. This energy consumption is broken down per housing type and energy carrier in Table 4.  
A descriptive division of the energy consumption can be made by dividing energy need into two distinct categories: heat loss compensation and operational needs, as illustrated in Figure 2.  
The building envelope is where the largest energy losses occur and household electricity is where the operational needs are largest, followed by hot water. On average the largest heat losses occur from exterior walls and windows, see Table 5. [16,17] has calculated energy loss and consumption related to the national building stock, while still accounting for the heterogeneity of the building stock in terms of construction year, typology _etc._  
\begin{table}
\begin{tabular}{c c c c c c c}  & & \multicolumn{2}{c}{**Percentage of**} & \multicolumn{2}{c}{**Hereof Percentage of Consumption for**} \\
**Energy Consumption** & & & & & **Heating and Domestic Hot Water by** \\
**in the Swedish** & **Sqm Floor** & **Total Energy** & & & **Energy Carrier** \\
**Building Stock, 2005** & **Space** & **Consumption** & & & **District** & **Electric** & **Sawdust,** & **Other** \\  & & & & **Heating** & **Heating** & **Wood, Pellets** & **Sources** \\ \hline Detached housing & 301 million m\({}^{2}\) & 45\% & 16\% & 45\% & 35\% & 4\% \\ \hline Multifamily housing & 238 million m\({}^{2}\) & 30\% & 93\% & 4\% & - & 3\% \\ \hline Commercial and public buildings & 128 million m\({}^{2}\) & 25\% & 83\% & 10\% & - & 7\% \\ \hline \end{tabular}
\end{table}
Table 4: Energy consumption per energy carrier in the Swedish building stock, 2005; Source: Boverket (2010); Mattsson (2010); SCB (2012) [16,17,26].  
Figure 2: Components of energy consumption and heat loss; Source: Boverket, 2010 (adapted to English) [16].  
Since this is technical data, it is presumed here to be indicative of the relative energy loss in Danish buildings, as well, although the claim cannot be substantiated. The aggregated energy saving potential in respect to the national energy accounts is significantly larger in detached houses than in apartment buildings both in Denmark and Sweden.  
Total energy consumption by Danish households represented 30.5% of total energy consumption in 2012, and 22.4% of total energy was consumed by households in detached houses. Household energy consumption was predominantly used for heating (81.9%, 2012), while 16.5% was used for electrical devises [19]. Thus, about 25% of total energy consumption in Denmark in 2011 was used for heating of private homes (18% detached housing and 7% multifamily housing).  
Summing up, the potential energy savings are likely to be larger on average when renovating the building envelope, particularly with measures targeting exterior walls and windows. This potential is likely to be more significant on average for detached houses relative to multifamily housing.