A heat pump hot-water heater is the best way to go for my setup.
I can get hot water from my boiler during the winter months,
but don't like the waste of running the boiler in the summer..
A heat pump hot-water heater would cool and dehumidify my basement during the summer. And, from what I've read, they don't use a lot of kWh,
when compared to heating elements.
What would be idea, is a 24 volt DC heat pump hot-water heater! That would
work way better than PV into resistance.. But, it would cost much more
and be more prone to breakdown.
According to the government studies that I've skimmed, the break-even for resistance hot-water heaters is the $1-a-watt panel..
Without a low priced panel, it's just something that most folks would not go for.
Except those guys who buy a new Prius with the built in solar roof..
They have mandated PV hot water on new houses and large renovations, in many areas down in Australia.
"
Hot water systems
A typical 1kW solar photovoltaic hot water system avoids around 1200-1500kWh of grid
electricity per annum, contributing to around 20% of residential sector greenhouse gas
emissions (The Nous Group 2007).
The Federal Government is currently giving consideration to a proposal to impose a
nationwide ban on electric hot water systems (HWS) in new housing in all States from 2010,
and for replacement HWS from 2012. Some States have already introduced such a ban, with
South Australia placing a ban on electric HWS for both new homes and replacement units in
existing homes on 1 July 2008, although the bans are conditional. This ban does not however
apply to homes in remote areas, multi-unit dwellings or a unit replacing one which services
only a shed or pool.
A ban on electric HWS in Queensland (implemented 2006) currently applies only to new homes
and substantial alterations and additions. It will be extended to apply to replacement units
from 2010. The ban will initially be voluntary for those without access to reticulated gas.
The NSW Building Code places an effective ban on the use of electric HWS in new housing and
for alterations and additions requiring planning approval. It is difficult to reach the BASIX
planning requirements without installing a low emissions hot water system.
"
http://www.caf.gov.au/documents/Acce...PRSReport3.pdf
I guess they are doing more than just studying PVHW Down Under
