Successful implementation of solar technologies relies on its integration with existing electrical networks, and the subsequent return on investment. When solar systems are constructed for self-consumption, their electricity will be diverted to the connection point, commonly known as tie-in points. These tie-in points are frequently connected to the microgrid of the consumer at the low voltage distribution board, and occasionally on medium voltage, where multiple transformers and distribution boards are fed from. Encompassed within the microgrid, transformers, power circuitry and equipment must accommodate the harmonics and cyclic loads from solar systems; most of which were designed and constructed without regard to the effects of solar systems. Excess electricity production from the solar system could enforce a functional change of the transformer from step-down to step-up–that is, not all the electricity is consumed at that particular tie-in point by the user and excess electricity is fed back into the microgrid. This study uses electricity production data to identify the impact on transformer maintenance, where it was found that neutral bus bar currents can increase nearly threefold if PV systems are not sized correctly. This will subsequently lead to transformer degradation, thus reducing lifespan. If grid penetration is increased beyond design specifications, transformers must be changed according to the foreseeable maximum load; reducing the system’s return on investment.