The operational cost benefit of green buildings
By Kagiso Sebetso
In addition to optimum environmental performance and high-quality indoor environment for occupants , the benefit of green buildings is to reduce the operational costs associated with water and electricity .
How is the operational cost saving determined ?
This is achieved on two levels :
1 . Modelled The subject building ’ s projected energy and water consumption are predicted through a building modelling process . A conventional ( non-green building ) version of the same building is also modelled as the base building . The difference between the two sets of results reflects the saving on the anticipated operational costs .
2 . Actual The subject building ’ s consumption data is collected daily through a building management system . The data is either measured against a modelled conventional version or measured against similar buildings . The outcome of the comparison reflects the saving on actual operational costs .
Who benefits from reduced operational costs ?
Tenants Tenants are the frontline beneficiaries of operational cost savings . This makes a significant difference to their overheads . An energy efficient building , without the additional benefit of solar PV can save up to more than 25 % on energy .
As an example , the following savings are predicted for the 5-star green design rated Prime Plaza II - Motswere :
• The building is predicted to use 20 % less energy than its equivalent conventional building .
• Not taking maximum demand savings into account , the energy consumption saving can translate up to a saving of P6,000 per month on electricity .
• Potential water cost savings of P7,000 per month are predicted when compared to the Green Star EWP tool ’ s benchmark .
Owner occupiers : When a green building is being occupied by its owner , rather than being rented out , the owner directly benefits from the operational cost savings . The owner is therefore able to pay-off the marginal capex of a green development through the operational cost savings which makes the green initiatives a form of investment for the owner .
Investors : Investors benefit indirectly from the operational cost savings on green buildings as their tenants enjoy these benefits . The indirect benefits to the investor include :
• Reduced tenant vacancies turnover as tenants would prefer to renew their leases to continue enjoying the operational cost savings .
• Reduced vacancy rates as the tenant operational cost savings create demand for the space .
• The higher demand for the property positively impacts the value of the property .
ISSUE 50 - JUNE 2022