Residential
PV systems are more often grid-tied without batteries
where solar PV markets are mature, sending all energy
into the grid.
Battery systems are necessary for off-grid applications
where utility is unavailable and occasionally installed
as backup power in applications where internal combustion
engine generators are not the preferred option.
Installed
cost for grid-tied systems will vary between $7 to $9
per watt depending on size and installation characteristics.
Installed costs for battery systems will vary much more
widely; somewhere between $10 to $15 per watt.
Commercial
PV systems are always grid interactive and use some of
the same PV modules as residential systems. Typically
the PV module will be selected because of the benefit
of cost, voltage and amperage characteristics.
Inverters can range from small to large depending on the
application. They will almost always be a three phase
configuration.
Installed
cost now ranges between $6 to $8 per watt for small commercial
and $5 to $7 per watt for large systems.
