On Commercial V. Residential Solar Installations

Sweet Spot Solar is delighted to see that a lot of commercial buildings including apartment complexes, warehouses, and large office buildings have expressed an interest in solar in recent months.

As a company whose focus is on providing the best quality product at the lowest price possible, we are uniquely positioned to work in this sector for several reasons.

First, the differences between commercial and residential solar applications have become less pronounced due to changes in technology. Our team members have been involved in some of BC's largest and smallest grid-tie solar photovoltaic arrays, and it's worth noting that some of the largest arrays in the province have been installed on residences.

Second, BC Hydro makes a distinction in terms of interconnection requirements between simple and complex distributed generation. In short, solar arrays less than 27 kW in size on a 200A or smaller service using Single Phase qualifies as simple in terms of the application process for net metering, whereas solar arrays up to 100 kW that don't meet these requirements are automatically defined as complex. We have done both kinds.

Third, the main difference between residential and most commercial arrays is that commercial properties often have flat roofs. We work with engineers through our supplier to design ballasted racking systems to work perfectly on flat roofs. Given the light weight of solar modules (typically less than 45 pounds) plus the balance of the system, these ballasted systems spread the load across rooftops very well. Here's an example of a system that our supplier provides for this application. For larger commercial installations, we use the consulting services of Sentinel Solar in Ontario to do system design.

For example, for a flat roof with dimensions of 73' by 137', our engineers estimated that 160 modules can be mounted on a ballasted rack angled at 15 degrees. Using 265W modules, this array would be rated at 42.4 kW DC. We provided recently a quote for an installed system like this for $140,000 all-in [$3.30/Watt installed is unbeatable].