Carbon footprints are high on the mind of energy users and it’s not just the power stations and aluminium producers. Many home owners , whether they are connected to gas or electricity , and every DIY practitioner , are  looking to achieve a lower carbon footprint .

This could be via solar hot water or gas. A solar panel home hot water system installation can often be justified with a faster return on your investment than a gas hot water system. Basically, water is heated in a “collector,” and stored in a tank as shown below.

This is a high cost upgrade and people get overloaded quickly with solar electric information BUT – probably the single best thing that you can do for your country: consider the numbers (sample only):

$8000 per Kilowatt is an average cost for solar panels

200 watt panel x 5 = 1,000 or 1 kilowatt KW

Average size system 3 kw cost $24,000*(sample price) = 15 panels

State rebates vary and tax credits will change from time to time.

Solar water heating systems are a mature renewable energy technology where the storage tank is horizontally mounted immediately above the solar collectors on the roof. No pumping is required as the hot water naturally rises into the tank or  where the storage tank is ground or floor mounted and is below the level of the collectors; a circulating pump moves water or heat transfer fluid between the tank and the collectors.

SWH systems are designed to deliver the optimum amount of hot water for most of the year. However, in winter there sometimes may not be enough solar heat gain to deliver sufficient hot water. In this case a gas or electric booster is normally used to heat the water.

What is the energy payback time on solar electricity for homes?

There is a lot of misinformation on this topic.  Depending on the type and size of panel used, payback periods range from a modest (5-10 years) to a very short (6-24 months).  Since most solar panels are expected to last twenty years or more, that means the amount of energy they produce will be somewhere between double, and 40 times, the amount of energy used to produce them. Selling surplus electricity back to the grid potentially enhances the viability of solar electricity and the cost of the renewable energy solution and as an alternative to gas based energy.

CHECK OUT THIS INFO ON BUILDING CHEAP SOLAR PANELS

For most home owners in Australia, the UK or the US,  in the short term it is cheaper to use a gas system than put in solar at this stage. Costs of panels are coming down and the DIY enthusiast will save money but for the moment the upfront costs in comparison to a gas system require a fairly long payback. In the medium term however, the DIY practitioner will be in a good position to take advantage of cheaper solar panels once they become available.

New coal gas fields being tapped in SE Queensland have yet defined the energy model for commercialising the business side of gas. Meanwhile other natural gas sources remain relatively low on the carbon footprint side as they often tap into existing infrastructure and hence have a lower payback period in any gas versus solar assessment.

Tags: renewable energy for water heating, Solar water heating