A 70% efficient power supply in a computer that needs 100 watts of power to operate will actually draw 130 watts (the extra 30 watts are lost as heat by the power supply). If a new 85% efficient power supply was installed the same system would then draw 115 watts.
1 The average prices for the basic cat blood work ranges from $75 to $175 per test. 2  It greatly depends on the type of test and how many tests are needed for your pet.
I'd guess $500 to $1000/year, depending on how expensive your food and vet is. The important part is that at some point there will be a $500 to $3000 vet bill that you weren't expecting. Last week my cat collapsed and it cost $1800 to diagnose and treat the problem, high blood pressure.