Performance & Monitoring14 August 20262 min read

What Percentage of Your Base Load Can 800W Solar Cover?

Your base load (fridge, router, standby) runs 24/7. Here's how much an 800W plug-in solar kit realistically covers in the UK.

🇬🇧This article is relevant for the UK market

What Is Base Load?

Your base load is the electricity your home consumes continuously — fridge, freezer, router, standby devices, alarms, clocks. A typical UK household's base load is 200-400W.

How Much Does 800W Solar Cover?

An 800W system doesn't produce 800W constantly. Daily generation follows the sun:

Time Typical output (sunny day, south facing)
7-8am 100-200W
9-10am 300-500W
11am-2pm 600-800W
3-4pm 400-600W
5-6pm 200-400W
7-8pm 50-150W

On a good summer day, your 800W system exceeds your base load for 8-10 hours, covering it completely during those hours.

Annual Base Load Coverage

Season Daily solar hours > base load Base load covered
Summer (Jun-Aug) 10-14 hrs 60-80%
Spring/Autumn 6-10 hrs 35-55%
Winter (Dec-Feb) 2-5 hrs 10-25%
Annual average ~40-55%

Real-World Savings

For a household with a 300W base load (£642/year at 24.5p/kWh):

Scenario Base load covered by solar Annual saving
Low (north, poor angle) 35% £225
Average (Midlands, south-facing) 45% £289
High (south, optimised) 55% £353

These figures represent the value of your base load coverage alone — additional savings come from running schedulable appliances during solar hours.


Can I cover my entire base load with solar?

Only during daylight hours. Without a battery, night-time base load must come from the grid. A battery system extends coverage into the evening.

What's the cheapest way to reduce base load?

Switch to LED lighting, use smart power strips to eliminate standby drain, and replace old fridges with A-rated models. Reducing base load by 100W saves £214/year.

Does a lower base load make solar less worthwhile?

Paradoxically, a lower base load means a higher percentage is covered by solar (less to cover). But the absolute saving is less. The calculator accounts for this.

See how much plug-in solar could save you — with real data for your postcode.

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