Jakes B November 4, 2019 05:25 AM I'm not sure from the article and video why they decided on the PV to Thermal chiller to Tank to Air conditioning route vs the more conventional PV to Inverter to AC voltage to Air conditioning option. Is the system "energy transfer" more efficient? Does the large thermal mass smooth out input supply variations stretching the cooling effect to after sunset? On colder days the air conditioning isn't using the max power available from the PV panels. With their Tank solution there is no option of using excess PV power in the rest of the facility. paul314 November 4, 2019 06:22 AM So how much did this system cost? PV prices look like about $1000/kw or a bit more, so may $3-4M including the water part? Which would put that $2-3M/year anticipated savings in perspective. (By shading the car parks they also likely prolong the lives of faculty and student cars by a fair bit.) El Greco November 4, 2019 06:33 AM Very nice! Do we know how much it cost? John November 4, 2019 08:33 AM How is a tank of water being labelled as a battery? Douglas Rogers November 4, 2019 10:28 AM My rooftop solar was $3000/KW and $2100/KW after tax rebate, for rated power of 7.5 KW. Actual peak power is 5.69 KW. Ima_Cynic November 4, 2019 12:15 PM My guess is the campus is already using chilled water cooling, and this addition simply replaces a portion of their cooling infrastructure, such as the cooling towers. A battery is simply an energy storage device. in this case, the tank is storing the solar energy spent to chill the water, and this is used to remove the heat rather than having to rely on other energy consuming devices to do so. Bazza Dagazza November 4, 2019 08:00 PM So let's see here... they save $100m over 25yrs = $4m/yr which represents 40% of their total energy bill which would be $10m/yr otherwise. There's a lot of missing information (intentional) which means you can't make any meaningful analysis of a project like this. A back of the napkin price estimate is at least $10m and probably closer to $15-20m. The estimated saving of $100m over 25 yrs is at a guess an over the top projection to justify the project. SOP for governments and bureaucrats. Interestingly enough you can dissipate heat into the ground. Ground temps often run around 6c year-round at about a 600mm depth. If you google map the site you'll notice there is a substantial area of open space near and around the water tank along with 2 small lakes/dams/ponds. Boondoggle keeps coming to mind for some reason...... J copley November 4, 2019 11:42 PM Same here. How much did this cost? No point spending $2 to save $1. Colt12 November 5, 2019 05:10 AM I'm sure that the engineers at the university and installation service have this figured out as a savings. MikeDalton November 5, 2019 05:57 AM The equivalent of 525 homes for 25 years. Are citizens really going to pay an average of AU$634 (US$438) per month for electricity over the next 25 years? That's some expensive power.