Backup power and solar calculators for OSBBs

Indicative calculations for a first conversation with the OSBB and specialists. This is not a power supply design, and results depend on your data and on the unconfirmed assumptions we show.

• OSBB backup power

  Indicative estimate of battery capacity, inverter power and surge power for backing up the common loads of an apartment building. The calculation is preliminary.

• Battery capacity

  Indicative battery capacity that accounts for depth of discharge, inverter efficiency, reserve, temperature and ageing. The assumptions can be changed.

• Inverter power

  Indicative continuous and peak inverter power that accounts for cos φ, starting currents and reserve. Motors require an engineering calculation.

• Solar panels

  Indicative peak power of a solar power plant (SPP) based on roof area. Energy yield is shown only from confirmed insolation data that you provide.

• Indicative cost

  A total for items whose prices you enter yourself: quantity, unit price, contingency. The calculator contains no prices of its own.

• Contribution per apartment

  How to split an OSBB fundraising amount between apartments in proportion to floor area: share of the total area, rate per square metre, contribution of one apartment. The formulas are shown and you enter the numbers.