Battery storage comes with its own vocabulary, and some of it is on your electricity bill. Each term has its own link, so you can send the one you need.
The utility meter that records your consumption in 15-minute intervals and sends it to MEA or PEA. Its interval data is what your demand charge is billed on, and the most useful single dataset for sizing a battery.
Charging the battery when grid power is cheap (off-peak) and using that energy when it is expensive (on-peak). The saving is the gap between the two rates, less what is lost in the round trip.
What your site would have drawn from the grid without the battery. Savings are measured against it, so it is agreed with you before the system runs, and our fee is a share of the difference.
The battery, the inverter that connects it to your site, and the controls that run it.
How fast a battery charges or discharges relative to its capacity. At 1C a battery can fill or empty in an hour; at 0.5C, in two. It sets how much power a battery of a given size can deliver.
PJJ's software layer over a battery: it forecasts the site, decides when the battery charges and discharges, recovers curtailed solar and watches cell health.
When solar panels could deliver more power than their inverter is rated for, the inverter caps its output and the top of the generation curve is cut off.
Solar your array could generate but does not, because the site cannot use it at that moment and cannot send it to the grid. The inverters throttle back and the energy is simply never produced, so it appears on no bill.
The part of a time-of-use bill charged per kilowatt of your highest demand in the month. It is set by the single highest 15-minute average during on-peak hours, so one short spike can set it for the whole month.
Fine metallic growths that can build up on a battery's electrodes over many cycles, reducing capacity. Electro-healing is aimed at them.
A low-current cycling routine, built into CESS, that smooths dendrite buildup in the cells.
A per-kWh charge added on top of the base energy rate on every Thai electricity bill. The Energy Regulatory Commission reviews it every four months to pass changes in fuel and power-purchase costs through to consumers.
A kilowatt (kW) is power, a rate at a moment; a kilowatt-hour (kWh) is energy, an amount over time. A battery has both: how much it holds (kWh) and how fast it can deliver it (kW).
The rated output of a solar array under standard test conditions. Real output is usually lower and varies with sun, heat and angle.
Thailand's two electricity distributors. The Metropolitan Electricity Authority serves Bangkok, Nonthaburi and Samut Prakan; the Provincial Electricity Authority serves the rest of the country. Their tariff structures are the same in shape.
A control method that plans ahead. At each step it optimises the battery over the forecast hours to come, carries out the first part of the plan, then plans again with fresh data. A rule-based controller reacts to what is happening now instead.
The two periods of a Thai time-of-use tariff. On-peak is 09:00 to 22:00, Monday to Friday. Off-peak is the rest: overnight on weekdays, and all day at weekends, on Labour Day and on ordinary public holidays. A compensatory holiday stays on-peak.
Discharging the battery during your highest on-peak demand, so the grid sees a lower maximum and the demand charge falls.
The inverter that converts the battery's DC to the site's AC and back. It is the equipment CESS sends charge and discharge commands to.
The share of energy put into a battery that comes back out. The rest is lost as heat in the cells and the inverter.
The share of your solar generation used on your own site rather than exported or curtailed.
How full the battery is right now, as a percentage of its usable capacity.
How much of its original capacity a battery still has. It falls slowly with age and use, and tracking it is how degradation is caught early.
A tariff that charges different rates at different times of day, plus a demand charge. Most Thai factories of any size are on one.
An inverter setting that stops a site's solar feeding power into the grid. Where a site has no agreement to sell power back, its solar is set this way, and whatever the site cannot use at the moment is curtailed.
Twelve months of billing data, and we will model your load, size the system and show you the whole financial case, including when the answer is not to build.
Or reach us at solarbuddies@pjjsolutions.tech