Batteries
Round-trip efficiency quietly taxes every unit you store
Energy put into a battery and taken out again arrives smaller than it left, and that shortfall sets the…
· 4 min read
Tara Mukherjee
Contributing editor, Power Your Roof
Tara writes about solar basics, batteries, bills & tariffs, mostly the parts other people skip and is happiest when a piece answers the question completely.
18 articles
Bills & Tariffs
Import and export are priced separately, and that changes everything
A solar household buys and sells electricity under two unrelated arrangements, and the gap between the two…
· 4 min read
Bills & Tariffs
Time-of-use pricing rewards moving a load rather than shrinking it
When electricity costs different amounts at different hours, the cheapest saving available is often a timer…
· 4 min read
Installation
What the roof has to carry is mostly wind, not weight
Panels add a modest dead load and a considerable uplift force, and it is the force trying to lift the array…
· 4 min read
Installation
String length is decided by the coldest morning of the year
A panel produces its highest voltage when it is cold, so the number of panels that may be wired in series…
· 4 min read
Efficiency
Hot water is the load most households never look at
Water has an unusually high heat capacity, so heating it is one of the largest energy demands in a home…
· 4 min read
Solar Basics
Ground mount versus roof, and what changes when the array leaves the building
A ground-mounted array buys ideal orientation, cool running and easy access, and pays for it in…
· 4 min read
Batteries
A car carries a far bigger battery, and it is usually somewhere else
Using a vehicle pack to power a house is technically real and practically constrained by availability…
· 4 min read
Efficiency
Sealing a house without ventilating it is how damp starts
Households generate several litres of water vapour a day, and the draughts that used to remove it are…
· 4 min read
Efficiency
The refrigerator never stops, which is why where it stands matters
A small load running every hour of the year outweighs large loads used briefly, and ambient temperature is…
· 4 min read
Solar Basics
Judging an array that somebody else had installed
Inheriting a system with a house means assessing hardware of unknown age against records that may not…
· 4 min read
Batteries
Surplus can go to the cylinder or to the battery, and they are not equivalent
A hot water diverter and a battery compete for the same spare kilowatt, and each wins in a different…
· 4 min read
Batteries
A battery is sized by the evening, not by the array
The useful capacity is set by how much electricity the household draws between sunset and sunrise, and most…
· 4 min read
Installation
Whether the house has one phase or three changes the whole design
Most homes are fed by a single leg of a three-phase network, and which arrangement arrives at the meter…
· 4 min read
Solar Basics
Trees complicate a solar site in a way that gets worse each year
A shading survey captures one moment, while the tree causing it is still growing, and the difference…
· 4 min read
Bills & Tariffs
A unit rate is several separate costs presented as one price
What looks like a single price for electricity is an assembly of wholesale energy, network charges, policy…
· 4 min read
Bills & Tariffs
Fixing an energy price buys certainty rather than a discount
A fixed contract is a hedge sold to a household, and like every hedge it is priced to be profitable for the…
· 3 min read
Installation
Earthing an array is about fault current, not about lightning
The green wire running back from the mounting rails exists so that a fault has a defined path and a metal…
· 4 min read