Solar Power for the Home..

derrilex

Is your hotty electric Brett ? If so, turn it down via the thermostat ( easy) but dont turn it down too far, just in the middle of the normal range is good.  Electric hotties are still just about the cheapest to run. Gas is no cheaper at all when bottle rental is included. Be careful with heat pumps too. Some work well others are dogs. Big electric hotties run on night rate are the best. Medium sized run on off peak are next best. I assume you guys would use a lot of hot water too.

UNM

Re: hot water. In VIC, legally whole  tank must  reach at least 60 degrees at least  once a week, or if element is part way up tank, 60 degrees every day. Required to kill legionella. If you shower in mornings, and have good insolation, then apricus evac tube with electric boost part way up tank works fine. Switched our boost off mid Nov, prob not required until end April. I was  told Dux are crap. Siddons heat pump systems apparently good. As for solar PV.  One of my clients bought a system that has six monthly PM (preventative maintenance) written into the contact and the installer has to be paid to clean it twice a year or warranty void

derrilex

Bloody tempering valves are a PITA. They must be fitted to any electric HWS and limit temp to 50 C by mixing cold water with the hot as the hot exits the HWS. Granted, as a safety feature for kids they are great but if you wash dishes old school you may as well piss in the sink, it wont be less cold. :D Fortunately, I have a dishwasher that only sees use once a week due to just the 2 lazy buggers dwelling here. Still, the dishwasher uses 13 lt of water, easily beating hand washing and rinsing ( thats my excuse anyhow)

Ol Grumpy

Kitchen sink and laundry are allowed full untempered hot water. I put in a new 3/4 hot and cold main with a 1/2 inch loop to all fixtures. Put in 3/4 tempering valve (Solar) on bathroom loops (6 outlets). 500 KPA PLV on cold main and Solar Hot Water... Council main runs at 650 KPA... Installed 420 Ltr Solar Hot Water with electric booster tank on ground with 3 panels on North roof. I can and often do boil the hot water tank.... The entire hot & tempered loop(s) is fully insulated for efficiency. Bottom line.... Oodles of HOT water with no waiting at full pressure to all outlets so two showers, dishwasher and a basin can all be used at the same time with no pressure drop, at any point & you can still flush a toilet, fill the kettle, etc without losing pressure in the showers... Hot water bill dropped from $700 qtr to $300 per qtr... I don't bother turning off the booster cause I removed the 3600 Watt element and put in a 1200 Watt element and that keeps up all year and is on night tariff anyway.... Oh yeah- cost me $600- for the whole hot water system- including RECS but excluding "insulation" $1,100 rebate... So Govt. paid me $500- more than my cost to do the job. Nice. It's not hard if you know what you are doing...