Batteries
Nameplate capacity and usable capacity are two different numbers
A home battery advertises the energy its cells contain, withholds a reserve you will never touch, and…
· 4 min read
Manish Trivedi
Deputy editor, Power Your Roof
Manish has been reporting on solar basics, batteries, bills & tariffs since long before it was fashionable and would rather show the working than assert the conclusion.
18 articles
Efficiency
Draught-proofing works on air exchange rather than on materials
Uncontrolled air movement carries heat out of a building through a route insulation cannot touch, and…
· 3 min read
Efficiency
Standby power is real and smaller than the folklore claims
The advice to switch everything off at the wall dates from equipment that no longer exists, and the…
· 3 min read
Efficiency
One degree on the thermostat, and the physics behind it
Heat leaves a building in proportion to the temperature difference across its fabric, which is why a small…
· 4 min read
Bills & Tariffs
What your metering arrangement is actually counting
The physical arrangement at the boundary decides whether generation, export and import are measured…
· 3 min read
Installation
Direct current is the part of a solar system that cannot be switched off
A lit array is live whatever the inverter is doing, and direct-current faults sustain arcs that…
· 4 min read
Installation
The gap behind the panels is doing more work than it looks
Air moving through the cavity between modules and roof carries away heat that would otherwise be paid for…
· 4 min read
Batteries
A storage system draws power simply to stay awake
Management electronics, conversion hardware and cooling all consume a little continuously, and on a lightly…
· 3 min read
Batteries
Filling a battery from the grid is a different proposition entirely
Storage without solar earns by moving consumption from an expensive period to a cheap one, which makes the…
· 4 min read
Bills & Tariffs
Chasing a self-consumption percentage can cost more than it saves
Self-consumption is a diagnostic ratio that got promoted to a goal, and households distort their lives to…
· 3 min read
Efficiency
A thermal bridge is a shortcut through the insulation
Heat concentrates wherever the path conducts best, so a small area of poorly insulated structure carries…
· 4 min read
Batteries
Leaving the grid entirely is a winter problem, not a battery problem
Disconnecting from the network means sizing storage against the worst week of the year rather than the…
· 4 min read
Bills & Tariffs
Changing supplier is harder once the roof is exporting
A generating household is running two arrangements at the same boundary, and the process that makes…
· 3 min read
Installation
Putting an array over a planted roof or a usable terrace
A green roof and a solar array can help each other, and a terrace and an array mostly compete, and both…
· 4 min read
Efficiency
A heat pump is sized from a heat loss calculation, not from the old boiler
The survey that should precede a low-temperature heating system works out how fast the building loses heat…
· 4 min read
Efficiency
Heat recovery ventilation and the retrofit it rarely justifies
A heat exchanger can warm incoming fresh air using the outgoing stale air, which works well in a very…
· 4 min read
Efficiency
A thermal camera shows surface temperature and nothing else
Infrared imaging is genuinely useful for finding where a building is losing heat, and it is misread…
· 3 min read
Efficiency
Thermal mass changes when a house is warm, not how much heat it loses
A heavy building stores heat and releases it slowly, which shifts the timing of everything and does nothing…
· 4 min read