Greywater & McHP

What is greywater?

• Leftover water from sinks, showers, and washing machines

• Highly purified water for drinking

• Water from natural sources like rivers and lakes

• Water that has been contaminated with sewage

Why Call it Grey?

• Because it comes from natural sources like rivers and lakes

• Because it is dirtier than blackwater

• Because it is highly purified water for drinking

• Because it is in between clean water and sewage water

Why should untreated greywater not be stored for long periods?

• It freezes

• It evaporates

• It promotes bacterial growth

• It solidifies

Answer explanation

Untreated greywater should not be stored for long periods because it promotes bacterial growth. This can lead to health risks and unpleasant odors, making it unsafe for reuse or disposal.

Which classification applies to greywater under regulations?

• Class 1

• Class 2

• Class 5

• Class 3

Answer explanation

Greywater is classified as Class 5 under regulations, indicating it is non-hazardous and can be reused for irrigation and other purposes, distinguishing it from more contaminated water types.

Which system component must be clearly labeled?

• Kitchen taps

• Garden hose

• Greywater pipework

• Electricity meter

Answer explanation

Greywater pipework must be clearly labeled to prevent contamination and ensure proper handling of non-potable water. This is crucial for safety and compliance with plumbing regulations.

What is the main output of a micro combined heat and power (micro‑CHP) system?

• Gas

• Water

• Heat

• Electricity

How much electricity can a typical domestic micro-CHP system generate once warmed up?

• Up to 2kW

• Up to 1kW

• Up to 3kW

• Up to 4kW

What is the driving heat source for micro‑CHP systems in the UK?

• Recovered heat

• Solar heat

• Biofuels

• Natural gas

Which technology is the most prevalent in today's domestic micro‑CHP market?

• Stirling engines

• Rankine engines

• Fuel cells

• Internal combustion engines

What is the typical efficiency of a stirling engine micro‑CHP system?

• Around 70%

• More than 90%

• Around 90%

• Less than 50%