Electric and gas hot water systems accounting for approximately 20% of a household's greenhouse gas emissions,and by installing a solar water system you will reduce these emissions and also save up to 75% of your water heating costs! Table below is sourced from the Debartment of Environment and Climate Change NSW.
How does solar hot water work
There exist two types of collectors:

• flat plate collectors (great for when tank must also be roof mounted)
• evacuated tubes (great for frost prone areas)

Flat plate collectors work on copper pipes running through a glass covered collector, often connected to a water storage tank on the roof. The hot water can then thermo-syphon itself in and out of the tank, thus heating the water. The updated option of flat plate collectors are evacuated tubes.

Evacuated tubes use a glass tube with a vacuum inside it and copper pipes running through the centre. The copper pipes are all connected to a common manifold which is then connected to a slow flow circulation pump which pumps water to a storage tank below, thus heating the hot water during the day. The hot water can be used at night or the next day due to the insulation of the tank.
The evacuation tube system are superior as they can extract the heat out of the air on a humid day and don't need direct sunlight. Due to the vacuum inside the glass tube, the total efficiency in all areas is higher.

Solar pool heating uses a similar technology to building / household solar hot water systems. Solar pool heating involves covering a roof with a black blanket of coils and pipes which also get heated by the sun combined with a slow flow pump which circulates the water through the panel and into the pool. Unfortunately Energy Matters only installs building / household solar water heating systems and does not perform installation of pool water heating systems.