Higher yes, enormous no, and the savings in energy use for transportation will outweigh the additional costs. In fact, lowering energy consumption is one of the primary advantages with an Ultra Compact City – second only to the city becoming a much more pleasant habitat to live in.
To start with electrical lighting, this is currently so efficient it matters far less than the energy used by the cars to move around. In the next few years LED lights will also be introduced to streetlights, something which will reduce energy consumption even more.
Some mechanical ventilation will be required, and will probably be a bigger consumer of energy, but it is unlikely to even closely rival the reduction due to reduced transportation requirements.