Browse Forums Building A New House 1 Jun 22, 2012 12:57 pm Is there a point of getting Solar Hot Water system and Solar Electricity? The way someone explained that to me, it didn't really makes much sense. Is it true that during the day you are using you electricity from your panels and the rest is going back into grid at small amount (let's say 4 cents). And if you need to use electricity during the night you'll be taking power from the grid and get charged about 40 cents. So anyway you'll end up paying for your electricity. The question is what is the point of spending thousands of dollars on Solar Electrical system if your power bill is still going to be almost as big. The other question is how does solar hot water system works? Does it work in a weird way too? If I want to have a shower in the early morning and the sun is not up yet, does it gets heated by the gas (hence gas charges apply) and what if I want to have a bath (for a sake of the argument) at night do I still get gas bill for that? The only water that will be "free of charge" would be water during the day, is that correct? I just want to know before I go forking out 4,5k for water and about the same amount for electricity. Originally we thought that by having solar electricity installed it will wipe out our electricity bill completely. We don't want to make any money on it (as i know some people do by pumping gazzilions into the grid), we just want zero-dollar bill. Any help would be appreciated. Thanks Re: Solar Systems (Gas and Electricity) 2Jun 22, 2012 1:10 pm Electricity supply companies have a bit of a problem with people's houses generating solar electricity. Everyone who generates electricity in the area covered by the supply company is generating it at the same time; and they're all NOT generating at the same time as well. There's no simple way for the electricity company to store all that electricity up during the day and feed it back during the night. So ... the end-result is that it's not economically viable for them, long term, to be able to take your solar-generated electricity during the day and sell it back to you at night at the same price. For this reason, I don't think that long-term you'll be able to avoid electricity costs by fitting solar cells and feeding excess into the grid. You should be able to reduce your costs a fair bit, but whether the reduced cost is enough to make up for the amount you pay for the system in the first point is a bit of a tricky question & depends on the incentives your state government pays for feeding power into the grid. Maybe try Googling for payback time on solar installations? To take your example, with the 4c and the 40c, it does kind-of work like that in some states. Other states work differently. However, if your billing uses a system called "net metering" (I think), then you only pay for the amount you're not using at any time. So imagine your house is using 500W of electricity, and your solar cells are generating 500W at the same time. You pay nothing for the electricity at this time, even if it is at the 40c rate. If your house is using 1000W and you are generating 500W, then you only pay for 1000 - 500 = 500W. It's when your house is generating 1000W and you are only using 500W, hence you're feeding more power into the grid than you are using, that they only pay you the 4c. Note I don't know the numbers/prices in WA, I'm just quoting your example back. Unfortunately the most expensive electricity prices are at night, when you can't generate anything from your solar cells. That's also the time everyone is having a bath, the TV is on, you're cooking etc. It's a bit of a bummer; the numbers don't work-out quite as badly as it sounds from what I'm writing, but with current technologies it does seem to me that you're better-off designing the house to not need the electricity rather than trying to make some of your own through solar cells. As for solar hot water, that's quite different, I believe the system heats the water but stores it in a tank until you use it. It's only if the water in the tank cools-down, and there's not enough sunlight around, that any extra heating from gas or electricity is required. I believe a properly-sized & installed solar hot water system should very rarely need this backup. Traditional electric hot water heaters running on off-peak power did much the same thing, only heating the water in the tank really late at night (except if the tank cools down too far in which case they can use mains power as a backup system). Re: Solar Systems (Gas and Electricity) 3Jun 22, 2012 1:27 pm AGF, I went into this in great detail before we made our decision. This is what I came up with. 1. Solar panels to Generate Electricity It was a lot more favourable when the credits for what you put back into the system was 47cents per kwh. Now it has reduced to 7cents the payback period is much longer but still works out over time. During the day you are generating electicity and what you dont use goes back into the grid. Your greatest saving is in the enregy that you generate that you use yourself which you are not paying Synergy 21cents per unit for. That is why it is good to have appliances such as washing machine, dishwasher etc operate during daylight hours. We have timer on ours so we can set the time we want it to start. The other benefit you get is that while your not home and little energy is being used your solar panels are genrating enrgy back into the grid and you are getting a small return - its sort of making a small contribution back to its cost. 2. Solar Hot Water Systems This is where you can get most of your savings. Solar HWS will heat up the water during the day and hold in storage tank. You can then use that during the day or night. There are two main tyypes of booster systems. electric boosters that reheat the water in the tank and instantanious gas which heat up water being drawn if it is below the set temperature. If you have a gas booster that will only comsume gas to heat up water if the tank temp is low and you are drawing water at the time. electric boosters normally heat up the water in tank so as you consume during the night it will automatically cut in and heat up water even if you dont need to draw on it, whereas the gas booster models will not heat up unless you are drawing oon it, they will sit and the water will be heated up next morning by the sun. We have had electric booster type for 30 years and it paid for itself many times over. Now we have the instananious gas type and I think the savings will be even greater. Definitely go for solar HWS, preferably gas booster, and I would still go for solar electicity panels as the cost of electricity is only going to increase at a much higher rate than CPI. I would personally not recommend going for too big a solar electricity system as the small amount that you get paid for what yuou put back into the system doesnt offset your capital cost. Just go for a system that will generate enough to offset a reasonable amount of your own useage. There are still pleanty of good deals out there. hope that helps, Tim Switch 830 in Meve Commenced 20/7/2011 Completed Early april 2012 Moved in 30/4/2012 Re: Solar Systems (Gas and Electricity) 4Jun 22, 2012 1:34 pm Thank you Forg and Tim. You were extremely helpful. Re: Solar Systems (Gas and Electricity) 5Jun 22, 2012 2:24 pm Yes thanks for that ... we have HWS but have been pondering solar panels for electricity .... FYI we are very happy with the savings in the gas bill now we have solar hot water ... about $80 a quarter for the last two bills For info on our build: viewtopic.php?f=31&t=43093 Built the McLaren by Dechellis - slab down 22 Feb - handover 30 Aug 2011 - and gardens finished 9 Dec 2012!! Re: Solar Systems (Gas and Electricity) 6Jun 22, 2012 7:19 pm With solar electricity it depends on your situation, our household has mum and two kids home during the day, so any solar power is consumed by the tv, computer etc saving us the 27c/kWh and rising! I also know people who have gone off grid with batteries and don't have electricity connected at all, they save a fortune! 2 Re: Solar Systems (Gas and Electricity) 7Jun 22, 2012 7:28 pm Mclaren Yes thanks for that ... we have HWS but have been pondering solar panels for electricity .... FYI we are very happy with the savings in the gas bill now we have solar hot water ... about $80 a quarter for the last two bills While I'm still tempted to do it ... isn't a solar hot water system around the $4.5k mark as opposed to about the $1.5k mark for a heat-pump off-peak system? Because $3k buys a lot of $80 quarters. That's about ... 11 years? Hmm, we intend to stay where we are for longer than that, which makes it sound worthwhile. Although we also want some solar cells, so I guess it depends on how much roof room we have. Re: Solar Systems (Gas and Electricity) 8Jun 22, 2012 7:52 pm I wouldn't recommend solar hot water, it will cost you more in the long run, i have a good mate who is a plumber and he is forever replacing or removing solar systems that are only a few years old. On the other hand I can highly recommend solar power, we installed a 2.5 kw system 12 months ago and have more than halved our power costs. Re: Solar Systems (Gas and Electricity) 9Jun 22, 2012 11:27 pm How good is the following HWS: http://www.rheem.com.au/Products/domest ... aterheater Can someone suggest any other if it's not good enough (2-3 people in the household, 2 bathrooms) Thanks Re: Solar Systems (Gas and Electricity) 10Jun 22, 2012 11:42 pm Forg Mclaren Yes thanks for that ... we have HWS but have been pondering solar panels for electricity .... FYI we are very happy with the savings in the gas bill now we have solar hot water ... about $80 a quarter for the last two bills While I'm still tempted to do it ... isn't a solar hot water system around the $4.5k mark as opposed to about the $1.5k mark for a heat-pump off-peak system? Because $3k buys a lot of $80 quarters. That's about ... 11 years? Hmm, we intend to stay where we are for longer than that, which makes it sound worthwhile. solar hot water system probably will last not more than 10-15 years anyway. Re: Solar Systems (Gas and Electricity) 11Jun 23, 2012 10:44 pm Can someone provide any feedback on Rheem 596270/2S-G ? Is this a good system? How does Rheem HWS rate overall? http://www.rheem.com.au//Assets/1164/1/ ... -F-WEB.pdf Thanks Re: Solar Systems (Gas and Electricity) 12Jun 24, 2012 1:53 am Most name brand HWS are good and its easy to find if its a dud by just going to google search and type in for example "Rheem HWS Problem". To understand the different HWS have a read of this information sheet. http://www.sustainability.vic.gov.au/resources/documents/Choosingahotwatersystem.pdf Here are some other brands http://www.solahart.com.au/ http://www.chromagen.com.au/solar-products/w1/i1001268/ http://www.dux.com.au/products/home http://www.rinnai.com.au/index.php?option=com_products&task=categories&cat_id=30&Itemid=2 Re: Solar Systems (Gas and Electricity) 13Jun 24, 2012 3:14 am Hi I would recommend instantaneous gas hot water unit either rinnai or dux and rheem are all good brands we have dux system supplies 20lts of hot water per minute very happy with it, don't go for storage as very expensive especially with gas prices going up as you are heating up a storage tank every time water is taken out and very annoying also if a few people have shower and water goes cold and recovery time takes a while. We have had 2 solar hot water systems in previous houses and they are great when it is hot weather but would not put one in again very expensive and you still end up paying extra for boosting when they are not working at there peak which is quite often when weather overcast and the winter when you want your water nice and hot not in the summer time. I have 22 solar panels and don't have any electricity bills we are in the process of selling our home and going to build another one in the country and most definately will put panels on roof again, not as many the next time but enough to have no energy bills as the sell back tariff will be obsolete by then. Hope this feedback helps. Re: Solar Systems (Gas and Electricity) 14Jul 03, 2012 1:27 pm Hi, We are building in an estate that requires solar hot water. Can anyone tell me if this is an ok brand and the best solar hot water type to have? How much is this going to save me on my bill compared to not having it? Vulcann VSi160 Solar hot water system with a 27L gas continuous flow booster (mounted in a recess box on wall of house) including 2 solar panels on roof. Thanks Re: Solar Systems (Gas and Electricity) 15Jul 03, 2012 3:14 pm Hills111 We are building in an estate that requires solar hot water. Check the estate's definition of their term "solar hot water". When we first started looking at building, my family informed me that from some-date-or-other, there would be no choice in NSW except to install solar hot water (noting that they were aware we don't have town gas). I've since discovered that the actual options include a heat-pump water heater; which in effect is just a way of heating the water in the same way as an electric heater always has, except using something that's kind-of like an airconditioner in reverse-cycle heating mode. I personally kind-of like the idea of solar hot water; I feel better paying some money up-front & getting stuff for free for a while after that, than having an ongoing regular cost. However, if you're allowed a heat-pump heater, it may suit you more. Can't hurt to ask, at least, IMHO. Re: Solar Systems (Gas and Electricity) 16Jul 03, 2012 3:49 pm our estate booklet says Instantaneous gas boosted solar hot water system or Instantaneous gas hot water system (5 star or better) plus a 1kw minimum photovoltaic solar array. We are happy to get it just wondering how much it will really save us in the long term. Re: Solar Systems (Gas and Electricity) 17Jul 03, 2012 6:04 pm Have a look at the Apricus systems. (Also called Thurmann and sold Reece. Rebadged Apricus) Evaporated tube systems are far more efficient than the flood panel systems. Just be wary where the tubes are sourced as some designs are more influenced by the sun. ie the angle of sunlight need is more than Apricus resulting in less heating time available. In relation to heat pump systems. If you live in a cold climate they are nowhere near as effective as if living in a warmer climate as they can freeze/become far less effective similar to air con systems We have just got a quote with electric backup (gas not viable when a bottle user) and for a 30 tube system approx $3700. Friends have similar systems and in our area turn the power backup off for 6-9 months of the year. If you have kids this is a huge saving in hot water bills. Settlement 1/2/12 New Shed 23/3/12 Slab poured 27/3/12 Frame complete 4/5/12 Roof complete 1/6/12 LOCKUP 29/6/12 Our new build blog http://kareenhillsownerbuild.blogspot.com/ I want to build a decking to the drawn shape outlined in black. The problem is how close can I build to the gas hot water unit? Will I be able to build around it and be… 0 20230 I looked into it a few years ago and my conclusion was to just build a carport that will support panels and get a system installed separately. The company I looked at had… 1 6481 4 10822 |